Oxidative reforming and electrolysis system and process for hydrogen generation

ABSTRACT

A process and system for generating hydrogen gas are described, in which water is electrolyzed to generate hydrogen and oxygen, and a feedstock including oxygenate(s) and/or hydrocarbon(s), is non-autothermally catalytically oxidatively reformed with oxygen to generate hydrogen. The hydrogen generation system in a specific implementation includes an electrolyzer arranged to receive water and to generate hydrogen and oxygen therefrom, and a non-autothermal segmented adiabatic reactor containing non-autothermal oxidative reforming catalyst, arranged to receive the feedstock, water, and electrolyzer-generated oxygen, for non-autothermal catalytic oxidative reforming reaction to produce hydrogen. The hydrogen generation process and system are particularly advantageous for using bioethanol to produce green hydrogen.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation-in-part under 35 USC § 120 of U.S. patentapplication Ser. No. 17/727,720 filed Apr. 23, 2022 in the names ofJeffrey Baker Harrison, Timothy Griffith Fogarty, Devendra Pakhare,Timothy David Appleberry, and Joshua Aaron Gubitz for OXIDATIVEREFORMING AND ELECTROLYSIS SYSTEM AND PROCESS FOR HYDROGEN GENERATION,and is a continuation-in-part under 35 USC § 120 of International PatentApplication PCT/US2022/079772 filed Nov. 11, 2022 in the names ofJeffrey Baker Harrison, Timothy Griffith Fogarty, Devendra Pakhare,Timothy David Appleberry, and Joshua Aaron Gubitz for OXIDATIVEREFORMING AND ELECTROLYSIS SYSTEM AND PROCESS FOR HYDROGEN GENERATION,and each of U.S. patent application Ser. No. 17/727,720, InternationalPatent Application PCT/US2022/079772, and the present application claimsthe benefit under 35 USC § 119 of U.S. Provisional Patent Application63/278,164 filed Nov. 11, 2021 in the names of Jeffrey Baker Harrison,Timothy Griffith Fogarty, Devendra Pakhare, Timothy David Appleberry,and Joshua Aaron Gubitz for OXIDATIVE REFORMING AND ELECTROLYSIS SYSTEMAND PROCESS FOR HYDROGEN GENERATION. The disclosures of U.S. patentapplication Ser. No. 17/727,720, International Patent ApplicationPCT/US2022/079772, and U.S. Provisional Patent Application 63/278,164are hereby incorporated herein by reference, in their respectiveentireties, for all purposes.

FIELD OF THE DISCLOSURE

The present disclosure relates to generation of hydrogen, and morespecifically to an integrated oxidative reforming and electrolysissystem and process producing hydrogen in an efficient, cost-effectivemanner. The system and process of the present disclosure can utilize avariety of feedstocks, and is particularly advantageous in applicationsutilizing renewable energy and renewable feedstock materials. Theintegrated oxidative reforming and electrolysis system and process mayalso be further integrated with (i) an ethanol refinery and/or (ii) aCO₂ processing or carbon capture plant, in various specificimplementations and embodiments.

BACKGROUND AND DESCRIPTION OF THE RELATED ART

Approximately 75 million metric tons/year of pure hydrogen are producedglobally. This hydrogen finds use in petroleum refining, steelproduction, food processing, and industrial manufacture of ammonia,methanol, and other chemical products.

In recent years, increasing efforts and resources have been directed toachieving efficient, cost-effective, and renewable generation ofhydrogen, thereby accelerating its acceptance and use as an energysource. Hydrogen is attractive for use in fuel cells to produceelectricity in a very efficient and environmentally advantageous manner,with the only byproduct being water. It is anticipated that hydrogenwill be increasingly used as an energy carrier to produce electricityfor mobile and small to medium scale stationary applications using fuelcells. This development will correspondingly stimulate the developmentof technologies for utilizing hydrogen as a clean fuel for vehicular andtransport power systems.

A fundamental issue associated with current hydrogen generation relatesto the fact that the vast majority of hydrogen is currently produced bysteam methane reforming (“SMR”). The hydrogen product of SMR is referredto as gray hydrogen, since SMR is a highly energy intensive process dueto the correspondingly high endothermic character of the reformingreaction, and releases substantial amounts of greenhouse gases into theenvironment. In consequence of such deficiencies, increasing attentionand investment is being directed to the development of green hydrogen,namely, hydrogen produced using renewable energy sources. In the UnitedStates, substantial efforts are focused on achieving green hydrogenproduction at a cost of $1 USD/kilogram H₂ by 2030.

Steam reforming of hydrocarbons other than methane can be performed, butthe associated reaction chemistry requires specialized equipment,metallurgy, and catalysts, as well as considerable added heat. As aresult, the high capital and operating costs make such steam reformingprocesses uneconomical for small-scale hydrogen generation.

Electrolysis of water is a process for hydrogen production, but lessthan 0.1% of global dedicated hydrogen production is derived from waterelectrolysis, as a result of its high cost and high energy requirements,since water hydrolysis requires considerable electricity in order todissociate water to yield hydrogen and oxygen. Although the thermalefficiencies of commercial electrolyzers are in the range of 60%-70%,when power line losses and other electricity conversion losses are takeninto account, overall energy efficiency of water electrolysis is in therange of only about 25-40%. Energy requirements of current electrolysissystems are in a range of 53.4-70.1 kWh/kilogram of hydrogen produced,and the cost of electricity for the energy-intensive water electrolysisprocess therefore is a significant factor in the high production cost ofhydrogen generated by such systems. This is true whether non-renewableor renewable electricity is utilized.

Faced with the foregoing problems, the art continues to seek newapproaches for generating hydrogen in an economic, efficient, andenvironmentally benign manner.

SUMMARY

The present disclosure relates to systems and processes for hydrogengeneration.

In one aspect, the disclosure relates to a hydrogen generation process,comprising: electrolyzing water to generate hydrogen and oxygen; andcatalytically oxidatively reforming a hydrocarbon feedstock with suchoxygen to generate additional hydrogen.

In another aspect, the disclosure relates to a hydrogen generationsystem, comprising: an electrolyzer arranged to receive water and togenerate hydrogen and oxygen therefrom; and a reactor containingoxidative reforming catalyst, arranged to receive a hydrocarbonfeedstock, water, and electrolyzer-generated oxygen, for catalyticoxidative reforming reaction of the hydrocarbon feedstock, water, andoxygen to produce hydrogen.

The disclosure in a further aspect relates to a coupled hydrogengeneration system, comprising a water electrolyzer, and a catalyticoxidative reforming reactor arranged to receive oxygen from the waterelectrolyzer.

Another aspect of the disclosure relates to a hydrogen generationprocess, comprising: (i) electrolyzing water to generate hydrogen andoxygen, and (ii) utilizing the oxygen from the electrolyzing to conductan oxidative reforming reaction.

A further aspect of the disclosure relates to a hydrogen productionprocess, comprising: (a) electrolyzing water to generate hydrogen gasand oxygen gas therefrom, the generated hydrogen gas being a firsthydrogen component of the hydrogen production; (b) adiabatically andnon-autothermally catalytically oxidatively reforming a feedstockcomprising at least one of an oxygenate and a hydrocarbon, with waterand with high purity oxygen comprising at least a portion of the oxygengas generated by the electrolyzing, to produce oxidative reformingreaction product gas containing hydrogen, CO, CO₂, methane, and steam;(c) catalytically reacting the oxidative reforming reaction product gasin a catalytic water gas shift reaction to convert at least part of theCO in the oxidative reforming reaction product gas to CO₂ and hydrogenby reaction with the steam therein, to produce a water gas shiftreaction product gas containing hydrogen, methane, CO, and CO₂; and (d)separating the water gas shift reaction product gas to recover hydrogengas therefrom as a second hydrogen component of the hydrogen production.

In another aspect, the disclosure relates to a hydrogen generationprocess, comprising: electrolyzing water to generate hydrogen andoxygen; and non-autothermally catalytically oxidatively reforming afeedstock fuel with said oxygen and with water to generate hydrogen,wherein the feedstock fuel comprises fuel selected from the groupconsisting of oxygenates, hydrocarbons, and mixtures thereof, whereinthe feedstock fuel may comprise bio-derived and/or non-bio-derivedconstituents, and may for example have a bio-derived content of up to100% by volume, based on total volume of the feedstock fuel, e.g., in arange of from 5% to 100% by volume, based on total volume of thefeedstock fuel, and wherein the reforming is conducted in a unitaryadiabatic reactor to which the hydrocarbon feedstock fuel, oxygen, andwater are introduced, and from which the generated hydrogen isdischarged, the unitary adiabatic reactor containing successive catalystbeds contacted in sequence in flow through the reactor, including (i) afirst catalyst bed comprising a partial oxidation catalyst, (ii) asecond catalyst bed comprising steam reforming catalyst, (iii) a thirdcatalyst bed comprising a high temperature water gas shift catalyst, andoptionally (iv) a fourth catalyst bed comprising a low temperature watergas shift catalyst.

Such hydrogen generation process may be carried out in another aspect,wherein the optional fourth catalyst bed is not present in the unitaryadiabatic reactor, but is present in a low temperature water gas shiftreactor external to the unitary adiabatic reactor.

A further aspect of the disclosure relates to a hydrogen generationsystem, comprising: an electrolyzer arranged to receive water and togenerate hydrogen and oxygen therefrom; and a non-autothermal oxidativereforming system comprising a unitary adiabatic reactor arranged toreceive oxygen from the electrolyzer, feedstock fuel from a feedstockfuel source, and water from a water source, the reactor containingsuccessive catalyst beds that are contacted in sequence in flow throughthe reactor, including (i) a first catalyst bed comprising a partialoxidation catalyst, (ii) a second catalyst bed comprising a steamreforming catalyst, (iii) a third catalyst bed comprising a hightemperature water gas shift catalyst, and (iv) a fourth catalyst bedcomprising a low temperature water gas shift catalyst, so that feedstockfuel from the feedstock fuel source with the oxygen from theelectrolyzer and water is catalytically oxidatively reformed in thereactor to generate hydrogen, the reactor being arranged to dischargethe generated hydrogen, wherein the feedstock fuel source is arranged tosupply feedstock fuel comprising fuel selected from the group consistingof oxygenates, hydrocarbons, and mixtures thereof, wherein the feedstockfuel may comprise bio-derived and/or non-bio-derived constituents, andmay for example have a bio-derived content of up to 100% by volume,based on total volume of the feedstock fuel, e.g., in a range of from 5%to 100% by volume, based on total volume of the feedstock fuel.

Such hydrogen generation system in another aspect may be constituted inan arrangement in which the optional fourth catalyst bed is not presentin the unitary adiabatic reactor, and is present in a low temperaturewater gas shift reactor external to the unitary adiabatic reactor in thehydrogen generation system.

The disclosure in another aspect relates to a thermally integratedhydrogen generation system, comprising: (A) an electrolyzer arranged toreceive water and to generate hydrogen gas and oxygen gas therefrom; (B)an oxygen storage vessel, arranged to receive the oxygen gas from theelectrolyzer; (C) a non-autothermal oxidative reforming systemcomprising a unitary adiabatic reactor arranged to receive oxygen gasfrom the oxygen storage vessel, feedstock fuel from a feedstock fuelsource containing the feedstock fuel, and water from a water source, theunitary adiabatic reactor containing successive catalyst beds that arecontacted in sequence in flow through the unitary adiabatic reactor,including (i) a first catalyst bed comprising a partial oxidationcatalyst, (ii) a second catalyst bed comprising steam reformingcatalyst, and (iii) a third catalyst bed comprising a high temperaturewater gas shift catalyst, so that the feedstock fuel from the feedstockfuel source with the oxygen from the oxygen storage vessel and the waterfrom the water source is catalytically oxidatively reformed in theunitary adiabatic reactor to generate oxidatively reformed gas that ispredominantly hydrogen, the unitary adiabatic reactor being arranged todischarge the generated oxidatively reformed gas, (D) a first heatexchanger arranged to receive the generated oxidatively reformed gasfrom the unitary adiabatic reactor and remove heat therefrom, to producea reduced temperature oxidatively reformed gas; (E) a low temperaturewater gas shift reactor arranged to receive the reduced temperatureoxidatively reformed gas from the first heat exchanger and convert atleast a portion of carbon monoxide in the reduced temperatureoxidatively reformed gas to carbon dioxide, to produce a low temperaturewater gas shift reaction gas of reduced carbon monoxide content, the lowtemperature water gas shift reactor including a fourth catalyst bedcomprising a low temperature water gas shift catalyst; (F) a hydrogengas purifier arranged to receive the low temperature water gas shiftreaction gas of reduced carbon monoxide content from the low temperaturewater gas shift reactor, and to produce a separated hydrogen gas, andwaste gas containing CO, CO₂, methane, and unrecovered (residual)hydrogen; (G) a hydrogen gas reservoir, arranged to receive the hydrogengas from the electrolyzer and the separated hydrogen gas from thehydrogen gas purifier; (H) a burner arranged to combust the waste gasproduced by the hydrogen gas purifier, containing CO, CO₂, methane, andunrecovered (residual) hydrogen, to yield a flue gas; (I) a second heatexchanger arranged to receive the flue gas from the burner for heatingof the oxygen gas from the oxygen storage vessel, the feedstock fuelfrom the feedstock fuel source, and the water from the water sourceprior to their introduction to the unitary adiabatic reactor; and (J) aprocess controller configured and arranged to coordinate operation ofthe electrolyzer and the non-autothermal oxidative reforming system inthe thermally integrated hydrogen generation system, and adjustthroughput of each of the electrolyzer and the non-autothermal oxidativereforming system to control temperature in the unitary adiabaticreactor, wherein the feedstock fuel contained in the feedstock fuelsource comprises fuel selected from the group consisting of oxygenates,hydrocarbons, and mixtures thereof, the feedstock fuel being of anysuitable type, including bio-derived and/or non-bio-derivedconstituents, and in various specific implementations employing afeedstock fuel having a bio-derived content of up to 100% by volume,based on total volume of the feedstock fuel, e.g., in a range of from 5%to 100% by volume, based on total volume of the feedstock fuel.

A further aspect of the disclosure relates to a hydrogen generationprocess, comprising operating the thermally integrated hydrogengeneration system described immediately above to perform a hydrogengeneration process comprising: electrolyzing water to generate hydrogengas and oxygen gas therefrom; and non-autothermally catalyticallyoxidatively reforming the feedstock fuel with the oxygen gas and withwater from the water source to generate hydrogen.

Other aspects, features and embodiments of the disclosure will be morefully apparent from the ensuing description and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B show a schematic flow sheet of a hydrogen generationsystem according to one embodiment of the present disclosure,integrating an oxidative reforming process system with a low temperatureelectrolysis system

FIGS. 2A and 2B show a schematic flow sheet of a hydrogen generationsystem according to another embodiment of the present disclosure,integrating an oxidative reforming process system with a hightemperature electrolysis system.

FIG. 3 is a schematic representation of a segmented adiabatic reactor ofa type useful for the hydrogen generation system and process of thepresent disclosure, in one embodiment thereof.

FIG. 4 a schematic representation of reactor internals showing anillustrative arrangement for minimizing pressure drop and/orfacilitating heat transfer from one catalyst bed to the next in asegmented adiabatic reactor according to another embodiment of thepresent disclosure.

FIG. 5 is a schematic illustration of a hydrogen generation systemincluding an integrated oxidative reforming and electrolysis plant asfurther integrated with an ethanol refinery and a CO₂ processing orcarbon capture system, according to another embodiment of thedisclosure.

DETAILED DESCRIPTION

The present disclosure relates to systems and processes for producinghydrogen in a cost-effective, efficient, and environmentallyadvantageous manner.

As used herein and in the appended claims, the singular forms “a”,“and”, and “the” include plural referents unless the context clearlydictates otherwise.

As used herein and in the appended claims, the term “about” in referenceto a numeric value means a range of corresponding values that may varyby +10% in relation to the numeric value.

As used herein and in the appended claims, the terms “biologicallyproduced” and “bio-derived” in reference to a feedstock fuel excludefossil fuel hydrocarbon feedstocks and fossil fuel hydrocarbon feedstockcomponents.

As used herein and in the appended claims, the term “high purity oxygen”refers to gas containing at least 98 mol % oxygen (O₂) and the term“high purity hydrogen” refers to gas containing at least 98 mol %hydrogen.

As used herein and in the appended claims, the term “predominantly” inreference to component(s) of a gas means that such component(s)constitute greater than 50 mol % of the gas.

As used herein and in the appended claims, the term “oxygenates” meanschemical compounds containing oxygen as part of their chemicalstructure, which can be non-autothermally oxidatively reformed toproduce hydrogen. Non-limiting examples of oxygenates include alcohols,e.g., methanol, ethanol, isopropyl alcohol, n-butanol, and tert-butanol,and ethers, e.g., methyl tert-butyl ether, tert-amyl methyl ether,tert-hexyl methyl ether, ethyl tert-butyl ether, tert-amyl ethyl ether,diisopropyl ether, glycols e.g. ethylene glycol, propylene glycol,butane diol, aldehydes e.g. fomaldehyde, acetaldehyde, and acids e.g.formic acid, acetic acid, lactic acid, and citric acid.

In all chemical formulae herein, a range of carbon numbers will beregarded as specifying a sequence of consecutive alternativecarbon-containing moieties, including all moieties containing numbers ofcarbon atoms intermediate the endpoint values of carbon number in thespecific range as well as moieties containing numbers of carbon atomsequal to an endpoint value of the specific range, e.g., C₁-C₆, isinclusive of C₁, C₂, C₃, C₄, C₅ and C₆, and each of such broader rangesmay be further limitingly specified with reference to carbon numberswithin such ranges, as sub-ranges thereof, within the scope of thepresent disclosure. Thus, for example, the range C₁-C₆ would beinclusive of and can be further limited by specification of sub-rangessuch as C₁-C₃, C₁-C₄, C₂-C₆, C₄-C₆, etc. within the scope of the broaderrange. In addition, ranges of carbon numbers herein may be furtherspecified within the scope of the disclosure to particularly exclude acarbon number or carbon numbers from such ranges of carbon numbers, andsub-ranges excluding either or both of carbon number limits of specifiedranges are also included in the scope of the disclosure.

The same construction and selection flexibility is applicable tostoichiometric coefficients and numerical values specifying the numberof atoms, functional groups, ions or moieties, as to specified rangesand numerical value constraints (e.g., inequalities, including “greaterthan” (>) or “less than” (<) constraints), as well as to oxidationstates and other variables determinative of the specific form, chargestate, and composition of chemical compounds, chemical species, andchemical entities, within the broad scope of the present disclosure.

As used herein and in the appended claims, the term “autothermalreforming” means a conversion process that is conducted with partialcombustion of a feedstock fuel in the presence of oxidant, using aburner for combustion, prior to contacting with oxidation catalyst, andthe term “non-autothermal oxidative reforming” means oxidative reformingthat is conducted without such combustion, and in which the conversionprocess is fully catalytic.

The disclosure, as variously set out herein in respect of features,aspects and embodiments thereof, may in particular implementations beconstituted as comprising, consisting, or consisting essentially of,some or all of such features, aspects and embodiments, as well aselements and components thereof being aggregated to constitute variousfurther implementations of the disclosure. The disclosure is set outherein in various embodiments, and with reference to various featuresand aspects of the disclosure. The disclosure contemplates suchfeatures, aspects and embodiments in various permutations andcombinations, as being within the scope of the invention. The disclosuremay therefore be specified as comprising, consisting or consistingessentially of, any of such combinations and permutations of thesespecific features, aspects and embodiments, or a selected one or onesthereof.

The present disclosure provides a hydrogen generation system and processthat avoids and/or overcomes the various problems discussed in theBackground and the Description of the Related Art section herein aspresent in prior conventional approaches to hydrogen generation. Thehydrogen generation system and process of the present disclosureintegrates water electrolysis with non-autothermal oxidative reforming,wherein oxygen generated as a byproduct of the water electrolysisreaction is advantageously used in the non-autothermal oxidativereforming (“OR”) reaction.

The oxidative reforming that is carried out in the integratedelectrolysis and oxidative reforming system of the present disclosure isnon-autothermal oxidative reforming, and such non-autothermal oxidativereforming advantageously is carried out in an adiabatic reactor systemso that no external heat other than preheating of reactants is requiredto sustain the conversion process.

A fundamental goal of the present disclosure is the integratedcombination of an electrolysis system with a non-autothermal oxidativereforming system to convert oxygenates and/or mixtures of oxygenates andhydrocarbons to produce predominantly hydrogen. In this integratedsystem, the primary source of oxygen is the electrolysis system, but theoxygen requirements of the integrated system may be supplemented byadditional high purity oxygen sources and supplies, including, withoutlimitation, cryogenic air separation plants, adsorbent-based airseparation systems such as pressure swing adsorption (PSA) plants,temperature swing adsorption (TSA) plants, pressure swingadsorption/temperature swing adsorption (PSA/TSA) plants, high purityoxygen pipelines, tanks, tube trailers, and other systems, equipment,and reservoirs that are effective to deliver high purity oxygen for usein the integrated electrolysis and non-autothermal oxidative reformingsystem.

Non-autothermal oxidative reforming in the hydrogen generation systemand process of the present disclosure may be carried out with anysuitable type or types of feedstock fuel, including non-bio-derivedfeedstock fuels and/or bio-derived feedstock fuels, such as feedstockfuels in which the bio-derived content of the feedstock fuel is up to100% by volume based on the total volume of the feedstock fuel e.g.,feedstock fuels containing bio-derived content in a range of from 5% to100% by volume, based on the total volume of the feedstock fuel.

The feedstock fuel utilized in the integrated electrolysis and oxidativereforming system of the present disclosure thus can be bio-derivedand/or non-bio-derived, and may comprise oxygenates, landfill gas,hydrocarbons, and combinations of the foregoing. Non-bio-derivedfeedstock fuels may for example comprise natural gas, C₂-C₁₅hydrocarbons, methanol, or blends of alcohols and/or hydrocarbons.Fossil fuel hydrocarbons can be used in combination with bio-derivedfuels, but it is a salient feature of various preferred embodiments ofthe hydrogen production technology of the present disclosure that thebio-derived content of the feedstock fuel is present at a concentrationof up to 100% by volume, based on total volume of the feedstock fuel,e.g., in a range of from 1% to 100% by volume, 5% to 100% by volume, orother suitable range or value of bio-derived content, based on totalvolume of the feedstock fuel.

In various embodiments, the bio-derived content of the feedstock fuelmay be in a range in which the lower end point value is 1%, 2%, 3%, 4%,5%, 8%, 10%, 12%, 15%, 18%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%,65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or up to 100%, and in which theupper end point value is one of the foregoing numeric values exceedingthe lower end point value.

The feedstock fuel may for example comprise gaseous and/or liquidhydrocarbons in the range of methane to diesel, especially those thatcan be produced biologically, but the disclosure is not limited thereto.As used in this context, diesel refers to hydrocarbon compositionsconstituted mainly of paraffins, aromatics and naphthenes, and containshydrocarbons with approximately 12 to 20 carbon atoms, with thecompositions having a boiling range from about 170° C. to about 360° C.When diesel compositions are employed, the diesel composition maycomprise biodiesel, or alternatively or additionally may comprisepetroleum-derived diesel. Other hydrocarbon compositions may beemployed, including single component hydrocarbon compositions as well asmulticomponent hydrocarbon compositions, of widely varying types.

Thus, the present disclosure encompasses the use of non-bio-derivedfeedstock fuels in the integrated electrolysis and oxidative reformingsystem of the present disclosure, such as for example natural gas,C₂-C₁₅ hydrocarbons, methanol, and alcohol/hydrocarbon blends, inembodiments in which the feedstock fuels contain no or substantially nobio-derived feedstock fuel components, as well as encompassing otherembodiments in which the non-bio-derived feedstock fuel component(s)is/are in mixture with bio-derived feedstock fuel component(s), as wellas encompassing still other embodiments in which the feedstock fuelscontain no or substantially no non-bio-derived feedstock fuels.

It correspondingly is a highly beneficial aspect of the integratedelectrolysis and oxidative reforming system and process of the presentdisclosure, that such system and process are able to operate on a widevariety of feedstock fuels, and that the feedstock fuel mix that isutilized may be varied depending on availability and cost of specificcandidate feedstock fuels. For example, bioethanol may be used as thefeedstock fuel during a period of low cost and ready availability ofbioethanol in relation to other candidate feedstock fuels, and thefeedstock fuel may be changed to another feedstock fuel, e.g., naturalgas, when bioethanol is not available or is relatively more costly ascompared to natural gas, or blends of various feedstock fuels may beutilized in which the relative proportions of various availablefeedstock fuel components are varied in relation to one anotherdepending on cost and availability, to achieve economical and efficientoperation of the integrated electrolysis and oxidative reforming systemand process.

In various embodiments of the oxidative reforming operation in theintegrated hydrogen generation systems and processes of the presentdisclosure, the non-autothermal oxidative reforming (OR) feedstock fuelmay include biological and fossil fuel-derived feedstocks, such asmethane, methanol, ethanol, propanol, butanol, glycerol, ethyleneglycol, diesel, or blends of two or more of the foregoing, but thedisclosure is not limited thereto. It will be recognized that inorganiccompounds and materials may be present in the feedstock, such as forexample phosphates and sulfur compounds, in various implementations ofthe non-autothermal OR operation. The non-autothermal OR feedstockspreferably are predominantly constituted by biological feedstocks, e.g.,biomethane, biomethanol, etc. Any suitable biofuels can be employed inthe non-autothermal OR feedstock.

In various preferred embodiments of the non-autothermal oxidativereforming operation in the integrated hydrogen generation systems andprocesses of the present disclosure, the non-autothermal OR feedstock isconstituted by, or includes, alcohols. Among alcohols, ethanol isparticularly advantageous, and may be renewable ethanol that is producedfrom corn, sugar cane, sugar beets, or other biomass withoutcontributing to greenhouse gas emissions. Ethanol is abundantlyavailable, since it is widely produced and supplied as an additive togasoline. Anticipated future declines in gasoline powered vehicles onroadways will result in ethanol production being increasingly allocatedto other applications, a circumstance that favors the implementation anduse of the hydrogen generation systems and processes of the presentdisclosure.

The integrated non-autothermal oxidative reforming and waterelectrolysis operations carried out in the systems and processes of thepresent disclosure enable the production of low-cost green hydrogen thatcan be utilized, for example, in fuel cells to produce electricity veryefficiently and cleanly, with only water as a byproduct.

The integrated non-autothermal oxidative reforming and waterelectrolysis systems and processes of the present disclosure may also beemployed in various embodiments to produce syngas (mixtures includinghydrogen (H₂) and carbon monoxide (CO) as predominant components) as aproduct gas, wherein CO₂ may be partially substituted for H₂O in theoxidant/reforming feed gas. Specifically, H₂O/CO₂ ratio may be in arange of from 0 to 20 (pure CO₂ to pure H₂O), e.g.,

H₂O/CO₂ = 0 2 CH₄ + O₂ + CO₂ = 3 H₂ + 3 CO + H₂O H₂O/CO₂ = 1 4 CH₄ +O₂ + CO₂ + H₂O = 9 H₂ + 5 COand the product gas may include syngas (CO, H₂, CO₂) wherein

(H₂ vol %−CO₂ vol %)/(CO vol %+CO₂ vol %)≥1.0.

While the integrated non-autothermal oxidative reforming and waterelectrolysis operations of the present disclosure are hereinafterillustratively described with reference to ethanol (C₂H₅OH) as thenon-autothermal oxidative reforming (OR) feedstock, it will beappreciated that the present disclosure is not limited thereto, and thatcorresponding implementations of the integrated non-autothermal oxygenreforming and water electrolysis systems and processes of the presentdisclosure can be carried out with any other suitable non-autothermal ORfeedstocks, including those disclosed by way of example hereinabove, aswell as others, including a wide variety of other hydrocarbon andhydrocarbyl feedstocks, in specific embodiments, implementations, andapplications of the present disclosure.

In the integrated non-autothermal oxidative reforming and waterelectrolysis operation of the present disclosure, the non-autothermaloxidative reforming may be carried out in the presence of suitablecatalyst at temperature that may for example be in a range of from about600° C. to about 1000° C., or in other suitable range of temperature. Inthis operation, C₂H₅OH is introduced into a non-autothermal reformer orreactor, where the liquid is thermochemically reduced intoshorter-chained carbonaceous species. These carbonaceous compounds reactwith steam in the presence of catalyst to produce a mixture of H₂ andother compounds, such as for example carbon monoxide (CO), carbondioxide (CO₂), acetaldehyde (C₂H₄O), ethane (C₂H₅), ethylene (C₂H₄), andacetone (CH₃COCH₃).

The catalyst used in the non-autothermal OR process may be of anysuitable type, and may for example comprise noble metal catalyst, mixedmetal oxide catalyst, perovskite catalyst, hexaaluminate catalyst,pyrochlore catalyst, or any other useful oxidative reforming catalyst.Non-autothermal OR catalysts useful in specific applications of thesystems and processes of the present disclosure include, in variousembodiments, catalysts comprising metals such as aluminum, zirconium,nickel, magnesium, gadolinium, yttrium, cobalt, cerium, ruthenium, noblemetals, etc. In various embodiments, catalysts such as the mixed metaloxide catalysts described in U.S. Pat. No. 10,688,472 may be employed.In various other specific embodiments, the catalyst may be a rutheniumcatalyst or a nickel catalyst, supported on a carrier such as alumina.In still other specific embodiments, the catalyst may be a platinumcatalyst or a palladium catalyst. Other specific embodiments may utilizea non-autothermal oxidative reforming catalyst including one or moremetals selected from Pt, Ni, W, Ru, Au, Pd, Mo, Cu, Sn, Rh, and V.Non-autothermal oxidative reforming catalysts in various additionalparticular embodiments may include one or more metals selected from Pd,Pt, Cu, Mn, and Rh. Further embodiments for carrying out thenon-autothermal oxidative reforming may utilize oxidative reformingcatalysts including metal(s) selected from Group VIII of the PeriodicTable.

Reforming processes invariably produce carbon monoxide (CO), and thewater gas shift (“WGS”) reaction is an important step in the reformingprocess. During the WGS reaction, CO is converted to CO₂ and H₂ throughreaction with steam.

In the non-autothermal oxidative reforming operation of the presentdisclosure, steam and oxygen are fed together as oxidants to reform thehydrocarbon feedstock into a H₂-rich product stream, which may be usedfor example in fuel cells or other H₂-powered apparatus. Non-autothermaloxidative steam reforming (OSR) is a combination of partial oxidationand steam reforming, in which oxygen and steam are fed to thenon-autothermal reformer vessel to utilize the heat generated from theexothermic partial oxidation of the hydrocarbon (e.g., ethanol) topromote the endothermic steam reforming reactions. By utilizing thegenerated oxygen from the water electrolysis reaction in the OSRreaction, the need for an air separation plant to generate oxygen forOSR may be avoided, which is advantageous in many implementations sincean air separation plant, whether cryogenic or adsorption-based, ishighly capital intensive in character. Nonetheless, in variousembodiments of integrated non-autothermal oxidative reforming andelectrolysis systems of the present disclosure, air separation plants,or other sources or supplies of oxygen may be utilized to supplementand/or buffer the oxygen needs of the non-autothermal oxidativereforming process.

Direct non-autothermal oxidative reforming of ethanol or other suitablefeedstock can be carried out by co-feeding steam and oxygen to thereformer vessel containing oxidative reforming catalyst, andcontemporaneously introducing ethanol or other suitable feedstock to thenon-autothermal reformer vessel. In the non-autothermal reformer vessel,when ethanol is utilized as the feedstock, reaction (1) is carried out:

C₂H₅OH+(3−2x)H₂O+xO₂→(6−2x)H₂+2 CO₂ ΔH_(25° C.)≈0 kcal/mole, whenx≈0.40  (1).

In various embodiments of the disclosure, wherein the feedstock isethanol, the non-autothermal oxidative reforming operation is carriedout, wherein 0<x<1.5. In various other embodiments, 0.10≤x≤1.1;0.3≤x≤0.9; 0.3≤x≤0.5; 0.75≤x≤0.85; or x may be in other rangesappropriate to the non-autothermal reformer vessel operation in theappertaining hydrogen gas generation system. In various specificembodiments, x may for example be about 0.4, 0.5, 0.65, 0.80, 1.0, orother suitable value that is appropriate for carrying out thenon-autothermal oxidative reforming operation.

In various embodiments in which the feedstock is ethanol, the hydrogenproduction process is carried out, wherein the non-autothermal oxidativereforming operation is conducted at a molar ratio of steam to ethanol ina range of from 0 to 6, and a molar ratio of oxygen to ethanol in arange of from 0.1 to 1.

As further specific examples for other feedstocks utilized in thenon-autothermal oxidative reforming operation, the following feedstocksand non-autothermal oxidative reforming reactions may be conducted inthe integrated oxidative reforming and electrolysis system and processof the present disclosure:

(A) Natural Gas (Methane)

2 CH₄+x O₂+(4−2x) H₂O=(8−2x) H₂+2 CO₂, wherein x is in a range of from0.5 to 2.0, and the non-autothermal oxidative reforming operation isthermally neutral at x=0.7;

(B) Methanol

CH₃OH+x O₂+(1−2x) H₂O=(3−2x) H₂+CO₂, wherein x is in a range of from 0.1to 0.5, and the non-autothermal oxidative reforming operation isthermally neutral at x=0.15;

(C) Hydrocarbons

C_(n)H_(m)+x O₂+(2n−2x) H₂O=(2n−2x+m/2) H₂ n CO₂, wherein x is in arange of from 0.4 to 14, for values of n=2-15;

(D) Glycerol

C₃H₈O₃+x O₂+(3−2x) H₂O=(7−2x)H₂+3 CO₂, wherein x is in a range of from0.2 to 1.2.

In this regard, it will be recognized that the stoichiometry of thenon-autothermal oxidative reforming reaction will vary with specificfeedstocks and feedstock blends. In the generalized situation in whichthe feedstock may be varied, with ethanol or hydrocarbon(s) other thanethanol being present, or when ethanol is present in a hydrocarbonmulticomponent feedstock, the non-autothermal oxidative reformingreaction of the hydrocarbon feedstock with oxygen and steam may becarried out, with oxygen being present in a range of from 5 volume % to95 volume %, based on the total volume of oxygen and steam in thenon-autothermal oxidative reforming reaction.

The hydrogen generation operation in accordance with the presentdisclosure may be carried out in a coupled reactor system in which awater electrolysis reactor is coupled with a non-autothermal oxidativereforming reactor, with byproduct oxygen from the electrolysis reactorbeing employed in the non-autothermal oxidative reforming reactor toachieve optimal hydrogen generation. The coupled reactor may beadvantageously designed for flexible operation, to allow for adjustmentin the throughput of the electrolysis reactor and the non-autothermaloxidative reforming reactor, in order to take advantage of variabilityin feedstock and electricity costs to provide the lowest-cost hydrogenpossible, thereby alleviating reliance on low renewable electricityprices.

Considering again reaction (1) above, in the operation of the coupledreactor system in which x=0.40, no external sources of heat are requiredto drive the reaction and it is correspondingly thermally neutral. Assuch, no excess heat is generated that must be removed and exhaustedinto the atmosphere or other heat removal systems or subsystems. Inconsequence, ethanol is not consumed for heating purposes, therebyrendering more of the ethanol feedstock available for conversion tohydrogen.

At values of x>0.40, the non-autothermal oxidative reforming becomesexothermic with the generation of additional heat that is potentiallyavailable for export to other processes or end-use facilities. Whilevalues of x greater than 0.40 decrease hydrogen production, when thenon-autothermal oxidative reactor is integrated with other processesrequiring heat, the combination enables higher total thermalefficiencies and lower capital and operating costs to be realized.

The integration of a water electrolyzer with the non-autothermaloxidative reforming operation in the hydrogen generation systems andprocesses of the present disclosure enables electricity to beeffectively utilized to split water into separate respective streams ofhydrogen and oxygen. The electrolysis reaction is endothermic requiringthe input of power to split the water molecules, which occurs by thefollowing reaction (2):

2H₂O→2H₂+O₂ ΔH_(25° C.)≈67 kcal/mol  (2)

The electrolyzer that is utilized in the hydrogen generation systems andprocesses of the present disclosure may be of any suitable type that isappropriate for splitting water molecules into separate streams ofhydrogen and oxygen. Such electrolyzer can range in size from small,appliance-sized equipment that is well-suited for small-scaledistributed hydrogen production, to large-scale central productionfacilities that can be connected directly to renewable or other forms oflow-cost electricity production. Low temperature alkaline electrolyzersor polymer electrolyte membrane (PEM) electrolyzers may be employed invarious embodiments of the hydrogen generation system. In otherembodiments of the hydrogen generation system, high temperature solidoxide electrolyzers exhibiting high efficiency with respect to powerconsumption may be utilized.

Electrolyzers useful in the practice of the present disclosure may thusbe of varying types, and may for example include: polymer electrolytemembrane (PEM) electrolyzers such as those commercially available fromPlug Power Inc., Latham, N.Y.; alkaline electrolyzers such as thosecommercially available from Nel ASA, Oslo, Norway; and solid oxideelectrolyzers such as those commercially available from Elcogen AS,Tallinn, Estonia.

Regardless of electrolyzer type, the respective hydrogen gas and oxygengas products discharged from the electrolyzer will contain some level ofwater vapor therein, and such discharged hydrogen gas and oxygen gas maybe dried or dehumidified, if and to the extent required, by use ofsuitable de-misters, dehumidifiers, condensers, etc.

In various embodiments of the integrated electrolysis and oxidativereforming system of the present disclosure, the electrolyzer isconfigured, constructed, arranged, and operated to produce from 15% to60% of the total hydrogen produced by the integrated electrolysis andoxidative reforming system, and to provide the full amount of oxygenrequired for the oxidative reforming while minimizing the powerrequirement of the electrolyzer in the integrated electrolysis andoxidative reforming system. In other embodiments, the electrolyzer isconfigured, constructed, arranged, and operated to produce from 25% to50% of the total hydrogen produced by the integrated electrolysis andoxidative reforming system. In still other embodiments, the electrolyzeris configured, constructed, arranged, and operated to produce from 35%to 45% of the total hydrogen produced by the integrated electrolysis andoxidative reforming system. Such operations of the electrolyzer mayadditionally in various embodiments concurrently provide all oxygenrequirements for burning of tail gas (the unrecovered (residual)hydrogen-, methane-, CO—, and CO₂-containing gas resulting fromseparation of water gas shift reaction product gas to recover hydrogengas) to provide for heating of reactants (feedstock, water, and highpurity oxygen) introduced to the oxidative reforming operation. Thecombustion of the unrecovered (residual) hydrogen-, methane-, CO—, andCO₂-containing tail gas, resulting from the separation of the water gasshift reaction product gas that is carried out to recover hydrogen gas,is highly advantageous for providing heating of the reactants introducedto the adiabatic reactor, and/or other heating requirements of theintegrated electrolysis and oxidative reforming system. The tail gas invarious embodiments may additionally comprise ethylene, as a constituentthat may provide additional heating value in the tail gas combustionoperation. In some embodiments, heat generated by the combustion of thetail gas may additionally be exported from the integrated electrolysisand oxidative reforming system. It may also be provided in theintegrated electrolysis and oxidative reforming system by heat fromother sources such as solar heating arrays, geothermal sources, etc., inthe broad practice of the systems of the present disclosure.

When the feedstock being processed in the catalytic reforming operationin the integrated electrolysis and oxidative reforming system is anethanol feedstock, such feedstock may derive from an ethanol refinery,and may for example comprise an ethanol distillate from a distillingoperation in the ethanol refinery, and/or may comprise ethanol from afermentation operation in the ethanol refinery without any subsequentdistillation or subsequent processing. The ethanol feedstock maycorrespondingly contain varying levels of water therein depending on theparticulars of the ethanol refinery processes from which the feedstockderives, e.g., water content of up to 10%, or even higher, by weight,based on total weight of the ethanol feedstock. The ethanol feedstock invarious embodiments may be hydrated or alternatively may be anhydrous incharacter. Ethanol feedstock containing water provides ethanol as wellas water reactant to the catalytic reforming operation. It willtherefore be appreciated that the integrated electrolysis and oxidativerefining process and system of the disclosure can accommodate ethanolrefinery feedstocks of varying character, which in addition to watercontent may comprise other components deriving from fermentationoperations or other processes in the ethanol refinery, depending on thecatalysts employed in the oxidative reforming and their compatibilitywith such components of the ethanol feedstock.

The catalytic reforming operation in various embodiments may be carriedout with predetermined or otherwise controlled molar ratios of steam toethanol, and predetermined or otherwise controlled molar ratios ofoxygen to ethanol. The molar ratio of steam to ethanol may for examplebe set or controllably maintained to be in a range of from 0 to 6, andmore preferably in a range of from 4 to 6, though the disclosure is notlimited thereto, and other ranges or values may be employed. The molarratio of oxygen to ethanol may for example be set or controllablymaintained to be in a range of from 0.1 to 1, and more preferably in arange of from 0.5 to 0.8, though the disclosure is not limited thereto,and other ranges or values of such ratio may be employed.

An important ancillary benefit of utilizing pure oxygen from theelectrolyzer in the oxidative reforming system is that it results in aproduct stream high in hydrogen and carbon dioxide that can be readilyseparated by membrane separation or pressure swing adsorption, toconcentrate the stream of carbon dioxide for low-cost CO₂ capture sothat the overall process is net negative in greenhouse gas emissionseven when using grid power for the electrolyzer.

The integrated electrolysis and oxidative reforming system of thepresent disclosure may be constituted as a stationary geographic siteinstallation, i.e., as a non-motive system, thereby avoidingdeficiencies and disadvantages associated with corresponding motive,e.g., vehicular, implementations. In such stationary installations, theelectrolysis system and the oxidative reforming system in theintegration are advantageously co-located with one another at a samegeographic site, enabling capital equipment expenditures to be minimizedand economies of scale to be achieved. Although a co-located integrationof the electrolysis system and oxidative reforming system is preferredin the majority of implementations, as for example wherein theelectrolysis system and the oxidative reforming system are within aseparation distance between each other that in various embodiments isless than at least one of 10 km, 8 km, 6 km, 5 km, 4 km, 3 km, 2.5 km,2.4 km, 2.3 km, 2.2 km, 2.1 km, 2.0 km, 1.9 km, 1.8 km, 1.7 km, 1.6 km,1.5 km, 1.4 km, 1.3 km, 1.2 km, 1.1 km, 1.0 km, 0.9 km, 0.8 km, 0.7 km,0.6 km, 0.5 km, 0.4 km, 0.3 km, 0.2 km, 0.1 km, 0.05 km, 0.025 km, 0.005km, and 0.001 km, the disclosure is not limited thereto, and theelectrolysis system and oxidative reforming system may be integratedwith one another in other embodiments at any other suitable separationdistances, and may even be sited remotely from one another at vastdistances while being integrated in the manner of the presentdisclosure, such as by flow circuitry, pipelines, and other integrationinfrastructure.

The present disclosure, in addition to fixed location, large-scaleintegrated electrolysis and oxidative reforming systems, such as thoseproducing 20,000-100.00 kg hydrogen/day, also contemplates a widevariety of other integrated electrolysis and oxidative reforming systemsconstructed and arranged to produce hydrogen at other and lesserproduction levels.

In various embodiments, the present disclosure contemplates modularintegrated electrolysis and oxidative reforming systems that may forexample produce hydrogen at levels on the order of 100-2000 kghydrogen/day. Such modular integrated systems are sufficiently compactto enable factory production of the systems and mounting of same onskids or in commercial containers for ready transport to andinstallation at hydrogen production sites for distributed generation ofhydrogen, e.g., at hydrogen fueling stations for motive vehiclesoperating on hydrogen fuel cells and/or internal combustion enginesfueled by hydrogen.

In various embodiments, the non-autothermal reactor system in theintegrated oxidative reforming system comprises a unitarynon-autothermal adiabatic reactor vessel in which is disposed a stagedassembly of catalyst beds, arranged so that exothermic reaction ofpartial oxidation takes place in a first stage, driving an endothermicreaction of steam reforming in a second stage resulting in a reductionin gas temperature from such endothermic second stage reaction, withwater-gas shift (WGS) catalysts being deployed in a high temperatureslightly exothermic third stage to convert carbon monoxide to hydrogen,so that the composition of the gas discharged from the vessel ispredominantly hydrogen. In various embodiments, the concentration ofhydrogen in the discharged gas may be greater than at least one of 50mol %, 55 mol %, 60 mol %, 65 mol %, 70 mol %, 75 mol %, 80 mol %, 85mol %, 90 mol %, 95 mol %, 98 mol %, and 99 mol %, and in variousembodiments the concentration of hydrogen in the discharged gas be in arange in which the lower end point value is one of the foregoing numericvalues and the upper end point value is one of the foregoing numericvalues exceeding the lower end point value, e.g., a range of from 50 mol% to 95 mol %, or 55 mol % to 85 mol %, or 60 mol % to 80 mol %, orother suitable range.

The unitary non-autothermal adiabatic reactor vessel in the integratedoxidative reforming and electrolysis system of the disclosure may beconstituted and arranged in a variety of different configurations in thebroad practice of the present disclosure, and may for example beconstructed to have a staged assembly of partial oxidation, steamreforming, and high temperature water gas shift reaction catalyst bedsdisposed in the adiabatic vessel as discussed above. In otherimplementations, the adiabatic unitary non-autothermal adiabatic reactorvessel may also contain therein a low temperature water gas shiftreaction catalyst bed, in addition to the partial oxidation, steamreforming, and high temperature water gas shift reaction catalyst beds.In still other implementations, the adiabatic reactor vessel may be maybe constituted and arranged so that it contains (i) at least onecatalyst bed capable of oxidative reforming of hydrocarbons andoxygenates, or (ii) a single catalyst bed that is a mixture of partialoxidation catalyst and steam reforming catalyst, or (iii) a singlecatalyst bed that is a mixture of a partial oxidation catalyst, a steamreforming catalyst, and a high temperature water gas shift catalyst, or(iv) two catalyst beds including a partial oxidation catalyst bedfollowed by a steam reforming catalyst bed, or (v) other suitablecatalyst bed or combination of beds.

Consistent with the foregoing, the integrated electrolysis andnon-autothermal oxidative reforming system may be constituted in variousembodiments with a high temperature water gas shift reaction catalystbed and a low temperature water gas shift reaction catalyst bed that arelocated downstream of the unitary non-autothermal adiabatic reactorvessel that is employed to conduct the partial oxidation and steamreforming operations. Accordingly, the unitary non-autothermal adiabaticreactor vessel conducting the partial oxidation and steam reformingoperations may be provided in a series arrangement with (i) a vesselcontaining the high temperature water gas shift reaction catalyst,followed by a vessel containing the low temperature water gas shiftreaction catalyst, or (ii) a vessel containing both the high temperaturewater gas shift reaction catalyst and the low temperature water gasshift reaction catalyst therein, e.g., in separate catalyst beds in suchvessel.

The integrated electrolysis and non-autothermal oxidative reformingsystem and process of the present disclosure may in various embodimentsbe constituted for hydrogen generation or alternatively for syngasgeneration, and may be integrated or co-located with a CO₂ capture andstorage system, e.g., being co-located at a stationary geographic siteinstallation, as for example with a separation distance between the CO₂capture and storage system and the oxidative reforming and electrolysissystem that is less than at least one of 10 km, 8 km, 6 km, 5 km, 4 km,3 km, 2.5 km, 2.4 km, 2.3 km, 2.2 km, 2.1 km, 2.0 km, 1.9 km, 1.8 km,1.7 km, 1.6 km, 1.5 km, 1.4 km, 1.3 km, 1.2 km, 1.1 km, 1.0 km, 0.9 km,0.8 km, 0.7 km, 0.6 km, 0.5 km, 0.4 km, 0.3 km, 0.2 km, 0.1 km, 0.05 km,0.025 km, 0.005 km, and 0.001 km, although the disclosure is not limitedthereto, and the respective systems may be integrated with one anotherat any other suitable separation distances, and may even be sitedremotely from one another at vast distances while being integrated inthe manner of the present disclosure.

The products of the oxidative reforming operation in the integratedelectrolysis and non-autothermal oxidative reforming system of thepresent disclosure are predominantly hydrogen and carbon dioxide(aggregately being 60 mol % or more of the discharged gas). In variousembodiments, the aggregated concentration of hydrogen and carbon dioxidein the oxidative reforming discharged gas may be greater than at leastone of 60 mol %, 65 mol %, 70 mol %, 75 mol %, 80 mol %, 85 mol %, 90mol %, 95 mol %, 98 mol %, and 99 mol %, and in various embodiments theconcentration of hydrogen and carbon dioxide in the oxidative reformingdischarged gas be in a range in which the lower end point value is oneof the foregoing numeric values and the upper end point value is one ofthe foregoing numeric values exceeding the lower end point value. Theintegrated electrolysis and non-autothermal oxidative reforming systemis desirably operated to produce a stream of high purity hydrogen,preferably having a hydrogen purity greater than at least one of 98 mol%, 98.5 mol %, 98.9 mol %, 99 mol %, 99.5 mol %, 99.9 mol %, 99.95 mol%, 98.99 mol %, and 99.999 mol %, or in a range in which the lower endpoint value is one of the foregoing numeric values and the upper endpoint value is one of the foregoing numeric values exceeding the lowerend point value.

Producing a stream of high purity hydrogen from the oxidative reformingsystem requires the provision of a separation system to recoverhydrogen, separating it from the hydrogen-containing stream comprisingcarbon dioxide, unreacted hydrocarbons, and carbon monoxide that isproduced by the oxidative reforming operation. After separation of thehydrogen, secondary/waste products generated by the hydrogen separation,e.g., tail gas containing carbon dioxide, unreacted hydrocarbons, carbonmonoxide, and unrecovered (residual) hydrogen, may be used to preheatthe oxidative reforming reactants prior to the conversion process. Ifthe waste stream from the hydrogen separation has sufficient caloricvalue, oxygen from the electrolysis system may be used in combustion ofthe waste stream to yield a flue gas of carbon dioxide and steam. Theflue gas may be processed to condense the steam, and the carbon dioxidecan be captured utilizing conventional methods and equipment, andoptionally sequestered by any of applicable sequestration techniquesknown in the art. Such operation of the integrated system yields anoverall hydrogen production from the integrated system that is negativein greenhouse gas emissions.

Referring now to the drawings, FIGS. 1A and 1B show a schematic flowsheet of a hydrogen generation system 100 according to one embodiment ofthe present disclosure, integrating a non-autothermal oxidativereforming process system 12 with a low temperature electrolysis system14.

The non-autothermal oxidative reforming system 12 includes awater-ethanol source (“Hydrocarbons/H₂O Blend”), from which an aqueoussolution of ethanol is delivered in the water-ethanol supply line 16with passage through heat exchanger 20 to the feedstock blender 18 formixing with oxygen supplied from the oxygen storage vessel 73 in oxygenfeed line 44. The resulting ethanol/water/oxygen feedstock stream isflowed in feedstock delivery line 22 through heat exchanger 24 to thenon-autothermal oxidative reforming reactor 28.

The non-autothermal oxidative reforming reactor 28 as schematicallyillustrated is a segmented adiabatic reactor containing an upper partialoxidation segment and including suitable catalyst for effecting partialoxidation of the feedstock introduced at suitable temperature (T_(OR))and pressure (P_(OR)) in feedstock delivery line 22. The temperature insuch initial partial oxidation segment (T_(S1)) may be in a range offrom about 700° C. to about 900° C., as appropriate to carry out thepartial oxidation of the feedstock. Proceeding in the flow direction ofgas flow through the adiabatic reactor, gas flowing from the initialpartial oxidation segment then flows through the intermediate reformingsegment containing suitable steam reforming catalyst so that steamreforming reaction is carried out at temperature (T_(S2)) in a range offrom about 450° C. to about 850° C., with gases then flowing from theintermediate (second) steam reforming segment through the third segmentof the adiabatic reactor containing high temperature water gas shiftcatalyst, in which high temperature water shift reaction is carried outat temperature (T_(S3)) that may be in a range of from about 300° C. toabout 420° C., to produce a reformate containing hydrogen that isdischarged from the adiabatic reactor in non-autothermal oxidativereforming reactor discharge line 30.

In the adiabatic reactor, the respective partial oxidation, steamreforming, and water gas shift reactions are catalytically carried outwith the temperatures in the respective partial oxidation (T_(S1)),steam reforming (T_(S2)), and water gas shift reaction (T_(S3)) segmentsbeing maintained so that T_(S1)>T_(S2)>T_(S3).

The oxygen storage tank 73 storing oxygen produced by the lowtemperature electrolysis system 14 and used to supply oxygen to thenon-autothermal oxidative reforming system 12 may be of appropriate sizeand capacity to effectively buffer the oxygen-generating capacity of thelow temperature electrolysis system 14, so that oxygen is sent from thelow temperature electrolysis system to such buffer storage tank, forsubsequent discharge therefrom to the oxygen feed line 44 in thequantity and at the rate required to supply the non-autothermaloxidative reforming system 12. In this manner, the low temperatureelectrolysis system and the non-autothermal oxidative reforming systemmay be selectively “matched” with one another in operation, with respectto operating conditions and throughput of both the electrolysis andnon-autothermal oxidative reforming systems of the integrated overallsystem.

Thus, in the operation of the illustrative FIGS. 1A and 1B system, inwhich ethanol is employed as a feedstock hydrocarbon, the ethanol iscatalytically reacted with oxygen and water in the non-autothermaloxidative reforming reactor 28 to form a mixture including hydrogen,carbon monoxide, water, and carbon dioxide, which then undergoes thehigh temperature water gas shift reaction whereby the CO is converted toCO₂ and H₂ through reaction with steam deriving from the wateroriginally supplied to the non-autothermal oxidative reforming systemfrom the water-ethanol source. The resulting gas is discharged from thenon-autothermal oxidative reforming reactor 28 in discharge line 30 andflows through the heat exchanger 20 to heat the aqueous solution ofethanol being introduced to the system in water-ethanol supply line 16,and then enters the low temperature water gas shift reactor 34, in whichat least a portion of the remaining CO in the stream is converted to CO₂and H₂. The resulting gas stream containing hydrogen and CO₂ isdischarged from the low temperature water gas shift reactor 34 in lowtemperature water gas shift reactor discharge line 36, and flows intohydrogen gas purifier 38.

In the hydrogen gas purifier 38, the water gas shift reactor effluentstream is separated into hydrogen, discharged from the purifier inhydrogen gas discharge line 40, and CO₂-containing waste gas, which isdischarged from the hydrogen gas purifier 38 in waste gas discharge line42. Hydrogen is flowed in the hydrogen gas discharge line 40 to thehydrogen gas storage reservoir 90 in the low temperature electrolysissystem 14, to supplement hydrogen gas that is produced by the lowtemperature electrolysis of water in the polymer electrolyte membrane(PEM) electrolyzer 66.

The hydrogen gas purifier while shown schematically by a unitary vesselin FIG. 1B may be of any suitable type, and may in various embodimentscomprise a single bed or alternatively a multi-bed pressure swingadsorption (PSA) unit in which each adsorbent bed undergoes activeadsorption operation and subsequent desorption/regeneration operationaccording to a predetermined sequence of operations. In otherembodiments, the hydrogen gas purifier may comprise a membraneseparation apparatus.

The low temperature electrolysis system 14 as schematically shown inFIGS. 1A and 1B includes a feed water source 50 from which feed water isflowed by the action of feed water pump 52 through the waterfilter/purifier 54 to the oxygen-water phase separation and supplyvessel 56. The oxygen-water phase separation supply vessel 56 supplieswater in water feed line 58 that is flowed by the circulation pump 60through heat exchanger 62 and ion exchanger 64 to the electrolyzer 66,whose cathode is connected by appropriate circuitry to a transformer andrectifier.

In the electrolyzer 66, the water is dissociated into hydrogen andoxygen, with the oxygen being flowed from the electrolyzer 66 in line 68to the oxygen-water phase separation and supply vessel. The oxygenentering the oxygen-water phase separation and supply vessel passesthrough the feed water therein and is discharged as an overhead streamin oxygen discharge line 72 containing oxygen demister vessel 70 andflow control valve 74.

From oxygen discharge line 72, the product oxygen stream from the lowtemperature electrolysis system 14 passes to the oxygen storage vessel73, from which oxygen is supplied in oxygen feed line 44 to thenon-autothermal oxidative reforming system 12 to provide oxygen for thenon-autothermal oxidative reforming that is conducted in non-autothermaloxidative reforming reactor 28.

The hydrogen that is generated by the water dissociation reaction inelectrolyzer 66 is discharged from the electrolyzer in hydrogen outletline 76 and flows to gas-liquid separator vessel 78 in which thehydrogen gas is disengaged from water, with the water being recycled tothe electrolyzer. A portion of the water recycled to the electrolyzermay be flowed in the electrolyzer recycle line 128 containing flowcontrol valve 130 to the intake of the circulation pump 60. The hydrogenis discharged from the gas-liquid separator vessel 78 as an overhead gasstream that flows in hydrogen delivery line 80 through the hydrogendemister vessel 82, heat exchanger 84, condensate trap 86, and flowcontrol valve 88 to the hydrogen gas storage reservoir 90, which aspreviously described also receives hydrogen from the non-autothermaloxidative reforming system in hydrogen gas discharge line 40.

Hydrogen gas from the hydrogen gas storage reservoir 90 may beselectively withdrawn from the reservoir in hydrogen discharge line 94and flowed to hydrogen compressor 92. The compressor compresses thewithdrawn hydrogen to appropriate pressure. The compressed hydrogen thenflows from the compressor in hydrogen supply line 96 containing flowcontrol valve 98 to a downstream use or transport destination, e.g., ahydrogen fuel cell, a hydrogen-utilizing chemical process facility, ahydrogen transport pipeline, or other use or disposition destination.

Thus, the hydrogen generation system 10 schematically depicted in FIGS.1A and 1B may be configured to enable the non-autothermal oxidativereforming system to operate in a thermally neutral manner (e.g.,corresponding to x≈0.40 in reaction (1)), and with the electrolyzerbeing sized and configured to provide the required amount of oxygen forthe non-autothermal oxidative reforming of ethanol for such thermallyneutral operation, so that no external source of heat is required, andno excess heat is produced.

The FIGS. 1A and 1B hydrogen generation system 10 may additionallycomprise a process controller 132 having bidirectional signaltransmission lines 134 and 136 coupled thereto and shown schematicallyto denote their coupling to process equipment components, such as pumps,compressors, flow control valves, heat exchangers, and sensors forsensing process conditions (e.g., temperatures, pressures, flow rates,and compositions, which sensed conditions are transmitted to the processcontroller by the signal transmission lines coupled to the sensors), formonitoring and controlling the process system. For such purpose, theprocess controller may comprise suitable signal processing componentsand processors such as computers, programmable logic control devices,etc., as appropriate for the monitoring and control operations to beperformed by the process controller.

For example, the process controller may be arranged to controltemperature in the unitary adiabatic reactor hereinafter more fullydescribed in connection with FIG. 3 hereof, so that partial oxidationreaction is carried out in the first catalyst bed at temperature in arange of from about 700° C. to about 900° C., steam reforming reactionis carried out in the second catalyst bed at temperature in a range offrom about 450° C. to about 850° C., and high temperature water gasshift reaction is carried out in the third catalyst bed at temperaturein a range of from about 300° C. to about 420° C.

In various embodiments, the process controller may be arranged tocoordinate operation of the electrolyzer and non-autothermal oxidativereforming system in the hydrogen generation system so that thenon-autothermal oxidative reforming system carries out the reactionC₂H₅OH+(3−2x) H₂O+x O₂→(6−2x) H₂+2 CO₂ wherein 0<x<1.5, or in a furtherspecific embodiment wherein 0.30<x<0.50, or in other embodiments inwhich x has other values or ranges, e.g., 0.10≤x≤1.1; 0.3≤x≤0.9;0.3≤x≤0.5; or 0.75≤x≤0.85; or x may for example be about 0.4, 0.5, 0.65,0.80, 1.0, or other suitable value, although the disclosure is notlimited thereto.

In various embodiments, the electrolyzer used in the hydrogen generationsystem may comprise a solid oxide electrolyzer, and the processcontroller may be arranged to coordinate operation of the electrolyzerand non-autothermal oxidative reforming system so that thenon-autothermal oxidative reforming system generates excess heat fortransfer to the solid oxide electrolyzer so that the solid oxideelectrolyzer operates at thermal efficiency greater than 50%.

By way of specific example, the FIGS. 1A and 1B hydrogen generationsystem 10 may be constructed and arranged as a 1500 kg H₂/day hydrogenstation for local filling operations, e.g., for fuel cell vehicles suchas automobiles, trucks, vans, forklifts, buses, robotic deliverycaddies, and other motive delivery and transport systems. Table 1 belowsummarizes the inputs and outputs of a 0.5 megawatt (MW) low temperatureelectrolyzer, and the inputs and outputs of a non-autothermal ethanoloxidative reformer, operating at x=0.40 (reaction (1)), in suchillustrative 1500 kg H₂/day hydrogen station.

TABLE 1 Operational Inputs and Outputs of 1500 kg H₂/Day HydrogenStation Inputs Outputs 0.5 MW Low Temperature Electrolyzer 1800 kgH₂O/day 200 kg H₂/day 11.0 MWh/day (at 55.7 kWh/kilogram H₂) 1600 kgO₂/day Non-Autothermal Ethanol Oxidative Reformer, Operating at x = 0.40(reaction (1)) 5750 kg ethanol/day (1920 gallons/day) 1300 kg H₂/day4950 kg H₂O/day (600 gallons/day) 11000 kg CO₂/day 1600 kg O₂/day

If the CO₂ produced from the non-autothermal oxidative reformer in theFIGS. 1A and 1B hydrogen generation system is derived from bioethanoland the electrolysis apparatus utilizes a green power source, the netcarbon dioxide balance for the overall system may approach zero. Invarious embodiments, the hydrogen generation system of the presentdisclosure may incorporate or utilize a CO₂ capture or CO₂ sequestrationsystem to provide a net negative CO₂ balance or emission. In variousembodiments, the respective non-autothermal oxidative reforming systemand the low temperature electrolysis system may be constructed andarranged to share various infrastructure components such as for examplea water treatment system, a control system, compression equipment, andhydrogen storage vessels. It will be recognized that the construction,arrangement, components, and operation of the hydrogen generation systemmay be widely varied in the broad practice of the present disclosure.

FIGS. 2A and 2B show a schematic flow sheet of a hydrogen generationsystem 100 according to another embodiment of the present disclosure,integrating a non-autothermal oxidative reforming process system 11 witha high temperature electrolysis system 126.

The non-autothermal oxidative reforming system in FIGS. 2A and 2B is ofa same generalized arrangement as the non-autothermal oxidativereforming system in FIGS. 1A and 1B, with a non-autothermal oxidativereforming reactor 28 that is supplied with oxygen in oxygen feed line 44from oxygen storage vessel 73, as previously described in connectionwith the hydrogen generation system of FIGS. 1A and 1B. Thecorrespondingly numbered components of the non-autothermal oxidativereforming system 11 are to be understood as corresponding to the same orsimilar numbered components as previously described in connection withthe hydrogen generation system of FIGS. 1A and 1B. The oxygen storagetank 73 in the FIGS. 2A and 2B system can be used to selectively“buffer” the overall operation of the non-autothermal oxidativereforming system and high temperature electrolysis system, similar tothe function and operation of the oxygen storage tank 73 in the FIGS. 1Aand 1B system, as previously described.

The high temperature electrolysis system 126 in the hydrogen generationsystem 100 of FIGS. 2A and 2B may utilize any suitable high temperatureelectrolyzer, such as for example a high temperature solid oxideelectrolyzer 102, for dissociating water into hydrogen and oxygen. Asschematically illustrated, the high temperature solid oxide electrolyzer102 is coupled by appropriate circuitry with a transformer andrectifier.

Makeup water is furnished to the high temperature electrolysis system inmakeup water supply line 110 and flows through heat exchanger 108 andheat exchanger 116 to the high temperature solid oxide electrolyzer 102.At the cathode of the high temperature solid oxide electrolyzer, ahydrogen/steam product stream is discharged in hydrogen/steam dischargeline 104 and passes through heat exchanger 108 and then to a knock-outpot 122, which may for example be operated at temperature of 32° C. orother suitable temperature or in other suitable temperature range ofoperation. The knockout pot 122 discharges a condensed recycle waterstream, and a product hydrogen stream that is discharged in hydrogendischarge line 124 and flowed to the hydrogen gas storage reservoir 90.

The high temperature solid oxide electrolyzer 102 at the anode thereofproduces an oxygen/steam mixture, e.g., at a 50/50 mole fraction ofoxygen and water. The 02/steam mixture is flowed in oxygen/steamdischarge line 106 through heat exchanger 112 to oxygen/water separator114. The oxygen/water separator 114 discharges the separated water, andthe correspondingly separated oxygen is discharged into oxygen feed line44 for flow to the oxygen storage vessel 73, from which oxygen issupplied to the non-autothermal oxidative reforming system 11.

In the high temperature electrolysis system 126, sweep water may beflowed to heat exchanger 112 and then to heat exchanger 118, and sweepsteam may be supplied from heat exchanger 118 to the high temperaturesolid oxide electrolyzer 102.

Thermal integration of the high temperature electrolysis system 126 andnon-autothermal oxidative reforming system 11 may be implemented using athermal recovery assembly 120, with a stream of hydrogen, carbonmonoxide, carbon dioxide, and water being flowed from thenon-autothermal oxidative reforming reactor 28 through a heat exchangerin the thermal recovery assembly 120, and with recirculation of flue gasin a flow circuit that includes heat exchanger 116, heat exchanger 118,and the heat exchanger in the thermal recovery assembly 120. The thermalrecovery assembly 120 may also include a thermal recuperator(“Recuperation”) for heat recovery. Such thermal recuperator may be ofany suitable type, and may for example be of a vertical flat panelconfiguration, or a horizontal flat panel configuration, or a cellularconfiguration, or more generally may be of a cross-flow, parallel flow,or rotary flow type, in various specific embodiments of the hightemperature electrolysis system. Any appropriate heat recovery elementsand/or devices may be utilized in such thermal recovery assembly,including heat pipes, thermal wheels, heat sinks, etc.

In a hydrogen generation system of the generalized type shown in FIGS.2A and 2B, the high temperature electrolyzer is sized to provide therequired oxygen to the non-autothermal oxidative reforming system suchthat the excess heat from the non-autothermal oxidative reformingreaction can be transferred and used efficiently to meet the thermalrequirements of the high temperature electrolyzer (solid oxideelectrolyzer in the embodiment illustrated in FIGS. 2A and 2B). Byoperating the non-autothermal oxidative reforming system to produceexcess heat, the high temperature electrolyzer is able to operate at animproved thermal efficiency, e.g., greater than 50%, and in variousembodiments on the order of 75% or higher. Unlike PEM or alkalineelectrolyzers, solid oxide electrolyzers can run at pressure levels thatare the same as the pressure levels at which the non-autothermaloxidative reforming system is operated.

In the hydrogen generation system illustratively shown in FIGS. 2A and2B, the product stream from the non-autothermal oxidative reformingreactor 28 is flowed at temperature T_(OR) and pressure P_(OR) to thehigh temperature electrolyzer heat exchanger in the thermal recoveryassembly 120, providing the required heat to convert water tohigh-temperature/high-pressure steam. Passing through this heatexchanger, the product gas from the non-autothermal oxidative reformingis reduced to an appropriate temperature T_(WGS) for the low temperaturewater gas shift reaction required to convert any carbon monoxide tocarbon dioxide, and flows to the low temperature water gas shift reactor34. In the low temperature water gas shift reactor 34, the productstream undergoes a catalytic shift reaction to reduce the CO content inthe product gas to suitably low level, e.g., less than 1 volume %, basedon the volume of the product gas.

The product gas from the low temperature water gas shift reactor 34flows to hydrogen gas purifier 38, in which the product gas is separatedinto hydrogen, discharged from the purifier in hydrogen gas dischargeline 40, and CO₂-containing waste gas, which is discharged from thehydrogen gas purifier 38 in waste gas discharge line 42. Hydrogen isflowed in the hydrogen gas discharge line 40 to the hydrogen gas storagereservoir 90 in which such hydrogen gas is stored with the hydrogen gasthat is produced by the high temperature electrolysis of water in thehigh temperature solid oxide electrolyzer 102.

The waste gas discharged from the hydrogen gas purifier 38 in waste gasdischarge line 42 flows to the oxygen/air burner 32 (“O₂/Air Burner”).The oxygen/air burner 32 is supplied with oxygen from oxygen storagevessel 73 flowing in oxygen feed line 44, via burner oxygen/air feedline 33. The oxygen/air burner 32 produces a flue gas that is dischargedin flue gas line 26, and flows through heat exchanger 24 for heating ofthe ethanol/water/oxygen stream being flowed to the non-autothermaloxidative reforming reactor 28, and the flue gas containing carbondioxide and water (CO₂/H₂O) is flowed as waste gas to the carbon dioxiderecovery vessel 46, where it is separated into a CO₂ stream, dischargedfrom the carbon dioxide recovery vessel 46 in carbon dioxide dischargeline 48, and a recycle water stream, discharged from the carbon dioxiderecovery vessel 46 in recycle water discharge line 49.

The CO₂ discharged in carbon dioxide discharge line 48 may be flowed toa CO₂-utilization facility, or to a CO₂ capture or sequestrationfacility, or to other disposition or use.

The recycle water stream discharged from the carbon dioxide recoveryvessel 46 in recycle water discharge line 49 may be recycled in thehydrogen gas generation system 100 to the electrolyzer, and/or may beutilized for forming the aqueous solution of ethanol and/or otherhydrocarbons (“Hydrocarbons/H₂O Blend”) that is combined with oxygen andflows as a feedstock to the adiabatic non-autothermal oxidativereforming reactor 28.

In a thermally integrated non-autothermal oxidative reforming system andhigh temperature electrolysis system, of a general type illustrativelyshown in FIGS. 2A and 2B, shared equipment coupled with efficiency gainsfrom thermal integration enables a compact hydrogen generation system tobe achieved, with substantially lower capital costs than would beincurred by use of either system alone.

The FIGS. 2A and 2B hydrogen generation system 100, similar to the FIGS.1A and 1B system previously described, may additionally comprise aprocess controller 140 having bidirectional signal transmission lines142 and 144 coupled thereto and shown schematically to denote theircoupling to process equipment components, such as pumps, compressors,flow control valves, heat exchangers, and sensors for sensing processconditions (e.g., temperatures, pressures, flowrates, compositions,which sensed conditions are transmitted to the process controller by thesignal transmission lines coupled to the sensors), for monitoring andcontrolling the process system. The process controller may beconstituted and operate as previously described for the processcontroller in FIGS. 1A and 1B, e.g., for controlling temperature in theunitary adiabatic non-autothermal oxidative reforming reactor so thatpartial oxidation, steam reforming, and water gas shift reactions arecarried out at predetermined temperature conditions, and/or forcontrolling other process conditions of flow rate, pressure,composition, etc. to achieve a desired output of hydrogen from theintegrated oxidative reforming and electrolysis systems in the hydrogengeneration system.

For example, in various embodiments, the process controller in the FIGS.2A and 2B hydrogen generation system may be arranged to coordinateoperation of the electrolyzer and non-autothermal oxidative reformingsystem in the hydrogen generation system so that the non-autothermaloxidative reforming system carries out the reaction C₂H₅OH+(3−2x) H₂O+xO₂→(6−2x) H₂+2 CO₂ wherein 0<x<1.5, or in a further specific embodimentwherein 0.30<x<0.50, or wherein x is in another suitable range ofvalues, e.g., 0.10≤x≤1.1; 0.3≤x≤0.9; 0.3≤x≤0.5; or 0.75≤x≤0.85; or x mayfor example be about 0.4, 0.5, 0.65, 0.80, 1.0, or other suitable value,although the disclosure is not limited thereto.

The process controller may additionally, or alternatively, be arrangedto coordinate operation of the high temperature electrolyzer andnon-autothermal oxidative reforming system so that the non-autothermaloxidative reforming system generates excess heat for transfer to thehigh temperature electrolyzer, e.g., solid oxide electrolyzer, so thatthe high temperature electrolyzer operates at thermal efficiency greaterthan 50%.

Table 2 below summarizes the inputs and outputs of a 1.2 megawatt (MW)high temperature electrolyzer, and the inputs and outputs of anon-autothermal ethanol oxidative reformer, operating at x=0.40(reaction (1)), in such illustrative 1500 kg H₂/day hydrogen station.

TABLE 2 Operational Inputs and Outputs of 1500 kg H₂/Day HydrogenStation Inputs Outputs 1.2 MW High Temperature Electrolyzer 4500 kgH₂O/day 500 kg H₂/day 27.8 MWh/day (at 55.7 kWh/kilogram H₂) 4000 kgO₂/day Non-Autothermal Ethanol Oxidative Reformer, Operating at x = 1.0(reaction (1)) 5750 kg ethanol/day (1920 gallons/day) 1000 kg H₂/day2250 kg H₂O/day (600 gallons/day) 11000 kg CO₂/day 4000 kg O₂/day

The hydrogen generation systems of the present disclosure mayincorporate and utilize various hydrogen purification apparatus,materials, and techniques to achieve a desired purity and composition ofthe product hydrogen from such systems. For example, contaminants andimpurities may be removed from the hydrogen product by use of physicaladsorbents, chemisorbents, condensation or solidification techniques,wet scrubbing, complexation and precipitation, or any other appropriatetechniques for the specific contaminant or impurity species involved.

It will be recognized that the hydrogen generation systems of FIGS. 1Aand 1B, and FIGS. 2A and 2B are shown in schematic renderings withoutreference to valves, pumps, compressors, etc. that may be implemented inthe respective systems as physically constructed, arranged, andoperated.

The integrated hydrogen generation systems of the present disclosure maybe configured and operated to carry out the non-autothermal oxidativereforming in a feedstock-flexible manner that accommodates a spectrum ofvaried bio-derived carbon-based feedstocks, by appropriate design orselection of oxidative reformer equipment and non-autothermal oxidativereforming catalyst. By such design and selection, a variety ofalternatively available feedstocks may be utilized, such as for examplebiomethanol, biodiesel, and biomethane, although the disclosure is notlimited thereto.

The integrated hydrogen generation systems of the present disclosure maybe implemented with high temperature water gas shift (HTWGS) reactionbeing carried out in the unitary adiabatic non-autothermal oxidativereforming reactor, and with low temperature water gas shift (LTWGS)reaction being carried out in a separate low temperature water gas shiftreactor, as illustratively shown in connection with FIGS. 1A and 1B, andFIGS. 2A and 2B. In other implementations of the integrated hydrogengeneration systems of the present disclosure, low temperature water gasshift reaction may be carried out in the oxidative reforming reactor, asa discrete segment of the reactor downstream of the high temperaturewater gas shift reaction segment, which in turn is downstream of thesteam reforming segment, which in turn is downstream of the partialoxidation segment. It will correspondingly be appreciated that theoxidative reforming reactor may be varied in its components andconstruction, within the broad scope of the present disclosure. Theoxidative reforming reactor thus may be a segmented reactor includingpartial oxidation, steam reforming, and high temperature water gas shiftsegments, with an optional low temperature water gas shift segment, assegments within a single reactor vessel. In such unitary oxidativereforming reactor, the respective partial oxidation, steam reforming,and water gas shift reactions can take place in a single vessel with thecatalysts for each reaction being segregated, e.g., by a porous ceramicor metal divider or other segregation structure or arrangement.

FIG. 3 is a schematic representation of a non-autothermal segmentedadiabatic reactor of a type useful for the hydrogen generation systemand process of the present disclosure, in one embodiment thereof.

As illustrated, the segmented adiabatic reactor is depicted in avertically upstanding orientation with an upper inlet end coupled with afeed conduit delivering ethanol (and/or other hydrocarbons or feedstockcomponents), water, and oxygen into the reactor vessel. The reactorvessel is of cylindrical configuration, having a circular cross-sectionin a transverse plane perpendicular to the flow direction of the gasesflowed through the reactor vessel. An upper inlet end cap or flange issecured to the upper end of the cylindrical housing of the reactorvessel, joined to the feed conduit, and defines an interior inletheadspace for receiving the ethanol, water, and oxygen reactants, forsubsequent downflow through the reactor to the lower discharge endthereof.

At the discharge end, a lower outlet end cap or flange is secured to thelower end of the cylindrical housing of the reactor vessel and definesan interior outlet plenum receiving the predominantly hydrogen andcarbon dioxide reaction products and unreacted reactant species from thesuccessive partial oxidation, steam reforming, and water gas shiftreactions, for discharge through the discharge conduit joined to thelower outlet end cap or flange.

The segmented adiabatic reactor may be formed of non-conductivematerial, and/or may be wrapped or coated with a thermal insulationmaterial, or otherwise may be constructed and arranged to establish andmaintain the adiabatic character of the reactor.

In the interior volume of the segmented adiabatic reactor, the differentcatalysts are arranged in vertically successive beds that may bephysically separated from one another by physical separation elements orstructure, e.g., screen elements, foraminous discs, porous frits, orother separation structures or arrangements that permit sequential fluidflow through the successive beds without excessive pressure drop orhydrodynamic flow anomalies such as channeling or dead spaces.

The uppermost catalyst bed comprises a partial oxidation catalyst (thecatalyst comprising, e.g., rhodium, palladium, platinum, rhenium,ruthenium, lanthanum, zirconium, strontium, calcium, yttrium, cerium,nickel, cobalt, or mixed metal oxide, or combinations or mixtures ofmetals and/or metal oxides) that mediates the predominantly partialoxidation exothermic reaction of the reactants at temperature that mayfor example be in a range of 700-900° C., although the disclosure is notlimited thereto.

The next lower catalyst bed comprises a steam reforming catalyst (thecatalyst comprising, e.g., promoted nickel, ruthenium, rhenium, rhodium,copper, zinc, cobalt, mixed metal oxides, or combinations or mixtures ofmetals and/or metal oxides, with specific embodiments utilizing supportssuch as alumina, silica, aluminosilicates, and with specific embodimentsutilizing promoters such as potassium, magnesium, strontium, calcium, orthe like) that mediates the endothermic steam reforming reaction of thepartial oxidation reaction products from the first (uppermost) catalystbed, with an upper portion of the promoted nickel catalyst bed being ata temperature that may for example be in a range of 700-850° C., andwith a lower portion of the steam reforming catalyst bed being at atemperature that may for example be in a range of 400-550° C., althoughthe disclosure is not limited to such temperature ranges, and othersuitable temperature conditions may be employed in the catalytic steamreforming reaction.

Under the steam reforming catalyst bed, the next lower catalyst bedcomprises a high temperature water gas shift catalyst (the catalystcomprising, e.g., iron, chromium, calcium, lanthanum, cobalt, strontium,platinum, copper-promoted iron, iron-chromium, copper, zinc,copper-zinc, nickel, iron oxide, chromium oxide, or other mixed metaloxides, or combinations and/or mixtures of metals or metal oxides)mediating the high temperature water gas shift reaction of theendothermic steam reforming reaction products. The high temperaturewater gas shift catalyst bed is at temperature that may for example bein a range of from 300-450-300° C., although the disclosure is notlimited thereto.

Although not shown in the illustrated reactor configuration in FIG. 3 ,the reactor in various embodiments may further include an optionalfourth catalyst bed comprising a low temperature water gas shiftcatalyst located inside the adiabatic reactor, or a separate lowtemperature water gas shift reactor vessel may be provided containingthe low temperature water gas shift catalyst, with the product gas fromthe adiabatic reactor flowing to the separate low temperature water gasshift reactor. The low temperature water gas shift catalyst may be ofany suitable type, and may for example comprise zinc, platinum,molybdenum, a copper-based catalyst such as copper, copper-zinc oxide,copper oxide, copper oxide-zinc oxide, copper oxide-zinc oxide-alumina,copper oxide-zinc oxide-chromium oxide or other mixed metal oxides ormixtures of metals and/or metal oxides.

By the successive reactions of partial oxidation in the first catalystbed, steam reforming in the second catalyst bed, and high temperaturewater gas shift reaction in the third catalyst bed, and optionally, asecondary low temperature water gas shift reaction in a fourth catalystbed, the reaction

C₂H₅OH+(3−2x)H₂O+x O₂→(6−2x)H₂+2 CO₂ ΔH_(298° C.)=0 kcal/mole, x=0.36

is carried out, and the hydrogen and carbon dioxide product stream,additionally containing unreacted reactants from the respectivereactions in the segmented adiabatic reactor, is discharged from thereactor in the product discharge conduit at the outlet end thereof.

It will be recognized that the specific catalyst materials describedabove in the description of the non-autothermal segmented adiabaticreactor are illustratively identified, and that other specific catalystmaterials may be utilized in various embodiments of the hydrogengeneration systems and processes of the present disclosure.

It also is to be recognized that although the reactor is illustrativelyshown and described with reference to FIG. 3 as having a verticallyoriented cylindrical conformation, with a circular cross-section, fordownflow gas flow operation, the present disclosure is not thus limited,and the reactor may be of any other suitable conformation, orientation,and flow configuration appropriate to the integration of the reactorwith the electrolyzer in the hydrogen generation system and process. Thereactor may have any suitable size, shape, orientation, andconfigurational character, including fixed beds, fluidized beds,rotating beds, motive belt beds, etc., and the reactor may have anyaspect ratio (e.g., length/diameter ratio) or other dimensionalcharacteristics, with cross-sections generally perpendicular to the flowdirection that are geometrically regular or irregular, etc.

FIG. 4 is a schematic representation of reactor internals showing anillustrative arrangement for minimizing pressure drop and/orfacilitating heat transfer from one catalyst bed to the next in asegmented adiabatic reactor according to another embodiment of thepresent disclosure.

The segmented reactor components depicted in FIG. 4 include a partialoxidation segment, which may comprise a high temperature resistantsupport for the partial oxidation catalyst, such as a monolith formed ofcordierite, alumina, iron-chromium alloy (e.g., FeCralloy, commerciallyavailable from Goodfellow Corporation, Coraopolis, Pa.), or othersuitable monolith or support material of construction, or extrudates, orpellets or spheres of such support material, or mixtures thereof, havinga partial oxidation catalyst, e.g., a rhodium-based catalyst, or othersuitable partial oxidation catalyst, on and/or in the monolith,extrudates, pellets, spheres, etc. The catalyst may for example bedeposited in the porosity of the support, or otherwise incorporated inthe support, in any suitable manner, such as by vapor deposition,solution impregnation, or other appropriate technique. The partialoxidation segment thus is arranged to receive the fuel (e.g., ethanol orother hydrocarbons or other feedstock), steam, and oxygen feed, with thegases preheated to “light off” temperature.

Following the partial oxidation segment, the steam reforming segment asthe next segment may comprise a high temperature resistant support forthe steam reforming catalyst, such as a catalyst-coated metal alloymonolith, or extrudates, pellets, spheres, or mixtures thereof formed ofcordierite, alumina, iron-chromium alloy (e.g., FeCralloy, commerciallyavailable from Goodfellow Corporation, Coraopolis, Pa.), as a supportfor the steam reforming catalyst. The steam reforming segment may forexample comprise a FeCr alloy monolith, having a nickel-based catalyst,or other suitable steam reforming catalyst, in and/or on the support.The steam reforming catalyst may be incorporated on and/or in thesupport by any suitable deposition, coating, or impregnation techniques.

Downstream from the steam reforming segment is the water gas shiftsegment as the next segment. The water gas shift segment may for examplecomprise a bed of pellets or extrudates of suitable support materialcontaining catalyst such as Fe—Cr catalyst on and/or in such support.The catalyst may be incorporated in the support material feedstock, byblending or mixing therein prior to the pelletizing or extrusionprocessing of the feedstock, or in other suitable manner such as vapordeposition, solution impregnation, or other incorporation techniques.

The respective segmented reactor components in the foregoing descriptionare of an illustrative character, and it is to be appreciated that othercomponents, supports, substrates, catalysts, and arrangements may bevariously employed in other embodiments of the present disclosure. Thesegmented components may be positioned and interfaced in the adiabaticreactor as appropriate to facilitate heat transfer through such reactorand to provide acceptable pressure drop for the gases flowing throughthe reactor from the reactor inlet upstream of the partial oxidationsegment to the reactor outlet downstream of the water gas shift segment.

The unitary adiabatic reactor utilized in the hydrogen generationsystems and processes of the present disclosure in various embodimentsmay be configured, constructed, and arranged to conduct (i) only partialoxidation and steam reforming reactions therein, or (ii) partialoxidation, steam reforming, and high temperature water shift gasreactions therein, or (iii) partial oxidation, steam reforming, hightemperature water gas shift, and the low temperature water gas shiftreactions therein, as may be desirable or otherwise appropriate inspecific implementations of the systems and processes of the presentdisclosure.

Although the unitary adiabatic reactor is described in variousembodiments herein as containing separate (segmented) beds of catalyst,wherein the catalyst in each separate bed is of a different type, tocarry out a specific one of the respective reactions conducted in thereactor, the disclosure also contemplates configurations andarrangements in which catalysts for conducting different ones of therespective reactions are in mixture with one another. For example, theunitary adiabatic reactor may contain a mixture of partial oxidationcatalyst and steam reforming catalyst as a corresponding single bed inthe reactor, upstream of a water gas shift reaction catalyst bed in thereactor. As another example, the unitary adiabatic reactor may contain amixture of partial oxidation catalyst, steam reforming catalyst, andhigh temperature water gas shift reaction catalyst as a correspondingsingle bed in the reactor, which may optionally be followed by a lowtemperature water gas shift reaction catalyst bed in the reactor if lowtemperature water gas shift reaction is to be carried out in the unitaryadiabatic reactor. The disclosure contemplates the provision of mixturesof the respective catalysts in which the respective catalysts arehomogeneously mixed with one another, as well as the provision ofmixtures in which the respective catalysts are heterogeneously mixedwith gradients of concentration in the unitary adiabatic reactor.

The unitary adiabatic reactor may be constituted with internal thermalmanagement components or features therein to facilitate or assist therespective reactions conducted in the unitary adiabatic reactor to becarried out at appropriate conditions. Such components and features maybe of any suitable type, and may for example comprise ceramic balls thatare localized in the reactor vessel or that are dispersed in one or moreof the catalyst beds to buffer or effectuate heat flows, or heattransfer rods, finned structures, or other heat transfer elements.

In a specific illustrative example, the unitary adiabatic reactor may beconfigured, constructed, and arranged to contain (i) a bed of suitablepartial oxidation catalyst such as a rhodium-substituted pyrochlorecatalyst, downstream of which is (ii) a bed of nickel-based reformingcatalyst.

In addition to the feedstock-flexible character of hydrogen generationsystems of the present disclosure, as earlier described herein, thehydrogen generation systems of the disclosure may be arranged andoperated to effectively “turn up” or “turn down” the non-autothermaloxidative reforming system and electrolysis system so as to optimize thehydrogen production from each unit based on current pricing offeedstocks (bioethanol, biomethanol, biodiesel, biomethane, etc.) andcurrent electricity prices. In this regard, the generation of greenhydrogen from renewable energy is associated with variable electricityprices. For example, the hydrogen generation system may be constructedso as to be readily reset, when high-grade ethanol feedstock is replacedwith low-grade ethanol or other biofuels. As a further example, thehydrogen generation system may be flexibly arranged to accommodatealternate uses for heat that is generated in the operation of theoverall system.

It will therefore be appreciated that the hydrogen generation systems ofthe present disclosure may be flexibly constructed and arranged toaccommodate a variety of different potentially available feedstocks,that high thermal efficiencies can be achieved since combustion offeedstock for steam reforming is not required, and that substantiallysimplified design and operation can be achieved by reduction of vessels,piping, valves, heat exchangers, etc.

The present disclosure thus provides a hydrogen generation system thatadvantageously integrates a water electrolysis system with anon-autothermal oxidative reforming system to enable low-cost generationof green hydrogen to be achieved. The hydrogen generation system permitsthe oxygen generated as a byproduct of the water electrolysis reactionto be utilized in a non-autothermal oxidative reforming systemprocessing ethanol or other biosourced feedstock, so that the couplednon-autothermal oxidative reforming and electrolysis systems are able togenerate green hydrogen in a highly cost-effective manner. Such couplednon-autothermal oxidative reforming and electrolysis systems can beflexibly operated in a variety of modes that selectively maximize eitherthe non-autothermal oxidative reforming or the electrolysis systemdepending on costs of feedstocks and electricity. The couplednon-autothermal oxidative reforming and electrolysis systems of thedisclosure produce low-cost green hydrogen that can be used in fuelcells to produce electricity in a clean and highly efficient manner,with water as the only byproduct. The green hydrogen may be used in fuelcells of various types, e.g., PEM fuel cells, and may be used in a widevariety of end-use applications, such as hydrogen combustion engines.

The present disclosure correspondingly provides, in a variety offlexibly configured implementations, a coupled hydrogen generationsystem, comprising a water electrolyzer, and a non-autothermal catalyticoxidative reforming reactor arranged to receive oxygen from the waterelectrolyzer. The disclosure additionally provides, in a variety offlexibly implemented forms, a hydrogen generation process, comprising:(i) electrolyzing water to generate hydrogen and oxygen, and (ii)utilizing the oxygen from the electrolyzing to conduct a non-autothermaloxidative reforming reaction.

The respective electrolysis and non-autothermal oxidative reforming insuch systems and processes can be arranged to operate at any suitablepressure conditions, including atmospheric, superatmospheric, andsubatmospheric conditions, and can be arranged to match up theelectrolysis and non-autothermal oxidative reforming operations toaccommodate variable energy supply conditions, variable temperatureconditions, and variable feedstock conditions. The oxygen generated inthe electrolysis operation can, in addition to supplying thenon-autothermal oxidative reforming operation, be exported from theprocess system to another, or other oxygen-using processes or systems.The non-autothermal oxidative reforming operation can be coupled withcarbon capture or carbon sequestration systems and processes, to provideenvironmental operation credits, e.g., carbon emission credits or otheroperational advantages.

In various embodiments, the electrolysis may be carried outcontinuously, intermittently, or in other modulated fashion toaccommodate variation in electricity costs, operating optimally whenelectricity is cheapest. The hydrogen generated in the electrolysis maybe utilized for generation of electricity, which then may be transmittedto electrical storage, such as large scale battery installations forbuffering of subsequent electricity needs of the electrolysis operation.

FIG. 5 is a schematic illustration of a hydrogen generation systemincluding an integrated oxidative reforming and electrolysis plant, asfurther integrated with an ethanol refinery and a CO₂ processing orcarbon capture system, according to another embodiment of thedisclosure.

An ethanol refinery produces ethanol as a fermentation product from afermentable feedstock. The fermentable feedstock may be a plant materialthat contains sugars enabling the fermentation to produce ethanol, orother starch- and sugar-based feedstocks such as sugar cane and sugarbeets, or cellulosic feedstocks comprising cellulose, hemicellulose, andlignin. Various grain materials may be employed as feedstocks for theethanol refinery, such as corn, rye, and wheat. Corn is a very commonlyused feedstock for ethanol production, and ethanol refineries using cornas a fermentable feedstock currently supply large quantities of ethanolfor use as a gasoline additive, and for use in an extensive range ofconsumer products.

FIG. 5 in the schematic depiction of the ethanol refinery shows ethanolrefinery components that may be conventionally present in an ethanolrefinery, but that are eliminated in the integration of the ethanolrefinery with the integrated oxidative reforming and electrolysis systemof the present disclosure.

Specifically, such eliminated components include downstream distillationcolumns that are rendered unnecessary by the direct use in the oxidativereduction system of dilute ethanol-water mixture distillate fractionsobtained from upstream initial distillation. In such manner, asimplified, truncated distillation unit can be employed.

Additional components of the conventional ethanol refinery that areeliminated in the further integration of the oxidative reforming andelectrolysis hydrogen generation system with the ethanol refineryinclude (i) the molecular sieve treatment unit that is utilized toremove water, which may for example be present at a level on the orderof 5 vol % in the ethanol produced by the conventional distillationequipment, (ii) the gasoline denaturant treatment that is utilized forcompliance with regulatory requirements for ethanol use as a gasolineadditive, or treatment of ethanol with other denaturants for ethanol usein other applications such as hand sanitizers, camp stove fuels,perfumes, etc., and (iii) the ethanol storage facilities conventionallyutilized for high-volume retention of product ethanol at the ethanolrefinery.

Thus, the further integration of the oxidative reforming andelectrolysis hydrogen generation system of the present disclosure withthe substantially smaller and simplified ethanol refinery achieves amajor reduction of the ethanol refinery footprint, and correspondingreduction in the capital equipment and operating costs of the ethanolrefinery.

The ethanol refinery as simplified in such manner may comprise theillustrated components shown in the FIG. 5 embodiment, of initial grainreceiving and storage facilities, in which corn or other feedstockdelivered to the ethanol refinery plant is placed in storage silos orother containers, from which it is transferred to a milling unit. Themilled feedstock then is passed to a cooking unit, with the cookingproduct then being introduced to a liquefaction unit in which the cookedmaterial is subjected to partial hydrolysis to reduce its viscosity forthe subsequent fermentation in the fermentation unit. The feedstockslurry from the liquefaction unit passed to the fermentation unit thenundergoes fermentation under controlled temperature and pressureconditions, with the fermentate from the fermentation unit then passingto the centrifuge separation unit, e.g., for separation of oil andsolids that are used for animal feed or other products, and recovery ofan ethanol-water solution that then is passed to the distillation unit.

In the distillation unit, the ethanol-water solution is distilled toreduce its water content and the resulting water-reduced ethanol-watersolution which may for example contain 40-50 vol % water then is flowedto the integrated oxidative reforming and electrolysis plant as afeedstock for the oxidative reforming operation including partialoxidation, steam reforming, and water gas shift reaction in the unitaryadiabatic reactor of the oxidative reforming system.

The ethanol refinery in the fermentation operation produces a CO₂ tailgas, and such CO₂ tail gas may be flowed together with CO₂ tail gas ofthe integrated oxidative reforming and electrolysis system to a CO₂processing or carbon capture plant. The CO₂ processing or carbon captureplant may be arranged for packaging of CO₂ as a carbonation gas orchemical synthesis reactant, or for delivery of CO₂ to pipeline ortransport facilities, e.g., tank truck, rail, barge, marine shipping,aircraft, or other motive transport facilities, or for carbon captureprocessing of the CO₂ to effect carbon sequestration or remediation.

In such further integrated oxidative reforming and electrolysis systemand ethanol refinery, the oxidative reforming and electrolysis plant maybe operated so that waste heat generated in the oxidative reforming orelectrolysis operations is exported to the fermentation unit and/or tothe distillation unit so that the overall integrated facility isthermally managed in a highly efficient manner.

The above-described further integration of the integrated oxidativereforming and electrolysis system with an ethanol refinery achieves ahighly advantageous production of hydrogen gas that leverages existingethanol refinery infrastructure and simplifies new ethanol refineryconstruction and operation, particularly when the integrated oxidativereforming and electrolysis system is co-located with the ethanolrefinery, e.g., at a stationary geographic site installation withseparation distance between the ethanol refinery and integratedoxidative reforming and electrolysis system being of a same or similardistance as the previously described separation distance betweenco-located electrolyzer and non-autothermal oxidative reforming systemfacilities.

Thus, the integrated oxidative reforming and electrolysis system and theethanol refinery may for example be geographically situated so that theyare co-located, e.g., with a separation distance between the ethanolrefinery and the oxidative reforming and electrolysis system that isless than at least one of 10 km, 8 km, 6 km, 5 km, 4 km, 3 km, 2.5 km,2.4 km, 2.3 km, 2.2 km, 2.1 km, 2.0 km, 1.9 km, 1.8 km, 1.7 km, 1.6 km,1.5 km, 1.4 km, 1.3 km, 1.2 km, 1.1 km, 1.0 km, 0.9 km, 0.8 km, 0.7 km,0.6 km, 0.5 km, 0.4 km, 0.3 km, 0.2 km, 0.1 km, 0.05 km, 0.025 km, 0.005km, and 0.001 km, although the disclosure is not limited thereto, andthe ethanol refinery and the oxidative reforming and electrolysis systemmay be integrated with one another at any other suitable separationdistances, and may even be sited remotely from one another at vastdistances while being integrated in the manner of the presentdisclosure, such as by flow circuitry, pipelines, and other integrationinfrastructure.

As a specific example of an integrated oxidative reforming andelectrolysis system, as further integrated with an ethanol refinery in a31,250 kg H₂/day hydrogen generation system including a 10.5 MW lowtemperature electrolyzer and non-autothermal ethanol oxidative reformeroperating at x=0.40 (reaction (1)), integrated with a 40,000 gallon/dayethanol refinery, with all of the ethanol production of the ethanolrefinery being dedicated to production of hydrogen in the furtherintegrated system, Table 3 below sets out a tabulation of operationalinputs and outputs for such further integrated hydrogen generationsystem.

TABLE 3 Operational Inputs and Outputs of 31,250 kg H₂/Day HydrogenGeneration System Inputs Outputs 10.5 MW Low Temperature Electrolyzer37,500 kg H₂O/day 4,170 kg H₂/day 232 MWh/day (at 55.7 kWh/kilogram H₂)33,330 kg O₂/day Non-Autothermal Ethanol Oxidative Reformer, Operatingat x = 0.40 (reaction (1)) 120,000 kg ethanol/day (40,000 gallons/day)27,080 kg H₂/day 103,125 kg H₂O/day (12,500 gallons/day) 230,000 kgCO₂/day 33,330 kg O₂/day

The further integration of the integrated oxidative reforming andelectrolysis system with an ethanol refinery thus provides a variety ofpotential benefits in the construction and operation of the ethanolrefinery, as well as synergy between the ethanol refinery and theintegrated oxidative reforming and electrolysis system. Specifically,such further integration (i) obviates the need for a full conventionaldistillation assembly since the oxidative reforming and electrolysissystem is operated with dilute ethanol feed produced by the ethanolrefinery, (ii) enables CO₂ tail gas from the oxidative reforming andelectrolysis system to be processed by CO₂ storage and transportfacilities at the ethanol refinery, or alternatively CO₂ capturefacilities at the ethanol refinery, that are provided for processing ofthe CO₂ tail gas from the ethanol refinery, or to effect carbon captureof such tail gas from the ethanol refinery, (iii) eliminates themolecular sieve, denaturant addition, and ethanol storage otherwiserequired at the ethanol refinery, and (iv) enables byproduct heat fromthe integrated oxidative reforming and electrolysis system to bebeneficially employed in the fermentation and distillation operationsconducted in the ethanol refinery.

Accordingly, the present disclosure contemplates a further integratedsystem, in which an ethanol refinery is integrated with the hydrogengeneration system of the disclosure, wherein the ethanol refineryproduces ethanol as a fermentation product from a fermentable feedstock,e.g., corn or other plant or feedstock material, and the ethanolproduced by the ethanol refinery comprises at least part of thefeedstock fuel for the non-autothermal oxidative reforming system.

The present disclosure additionally contemplates a further integratedsystem, in which the ethanol refinery and hydrogen generation system arefurther integrated with a CO₂ processing or carbon capture system, withthe CO₂ processing or carbon capture system being arranged to receiveCO₂ gas from each of the ethanol refinery and the hydrogen generationsystem.

It will therefore be appreciated that the electrolysis andnon-autothermal oxidative reforming may be integrated in various waysand in various arrangements for green hydrogen generation, within thebroad scope of the present disclosure, and that the electrolysis andnon-autothermal oxidative reforming may be co-located with one anotherand with other processes and apparatus, to achieve hydrogen generation,oxygen generation, non-autothermal oxidative reforming, electricitygeneration, biomass conversion, CO₂ generation, and various otheroperations, in an efficient, cost-effective, and environmentally benignmanner.

In the practice of the present disclosure, a preferred implementation ofthe process of the present disclosure, in various embodiments, may beconstituted as a hydrogen generation process, comprising: electrolyzingwater to generate hydrogen and oxygen; and non-autothermallycatalytically oxidatively reforming a feedstock fuel with said oxygenand with water to generate hydrogen, wherein the feedstock fuelcomprises fuel selected from the group consisting of oxygenates,hydrocarbons, and mixtures thereof, wherein the feedstock fuel has abio-derived content of up to 100% by volume, based on total volume ofthe feedstock fuel, e.g., in a range of from 5% to 100% by volume, basedon total volume of the feedstock fuel, and wherein the reforming isconducted in a unitary adiabatic reactor to which the hydrocarbonfeedstock fuel, oxygen, and water are introduced, and from which thegenerated hydrogen is discharged, the unitary adiabatic reactorcontaining successive catalyst beds contacted in sequence in flowthrough the reactor, including (i) a first catalyst bed comprising apartial oxidation catalyst, (ii) a second catalyst bed comprising steamreforming catalyst, (iii) a third catalyst bed comprising a hightemperature water gas shift catalyst, and optionally (iv) a fourthcatalyst bed comprising a low temperature water gas shift catalyst. Suchpreferred process implementation may further embody or incorporate anyone or more compatible features (1)-(12) of:

-   -   (1) the bio-derived content of the feedstock fuel is up to 100%        by volume of the feedstock fuel, e.g., being in a range in which        the lower end point value is 1%, 2%, 3%, 4%, 5%, 8%, 10%, 12%,        15%, 18%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%,        75%, 80%, 85%, 90%, 95%, 98%, or up to 100%, by volume, based on        total volume of the feedstock fuel, and in which the upper end        point value is one of the foregoing numeric values exceeding the        lower end point value and up to and including the value of 100%        by volume;    -   (2) the feedstock fuel comprising a biologically produced        hydrocarbon;    -   (3) the feedstock fuel comprising a biologically produced        oxygenate;    -   (4) the feedstock fuel comprising ethanol;    -   (5) the electrolyzing being carried out in an electrolyzer        selected from the group consisting of polymer electrolyte        membrane electrolyzers, alkaline electrolyzers, and solid oxide        electrolyzers;    -   (6) the partial oxidation catalyst in the first catalyst bed        comprising a rhenium catalyst, the steam reforming catalyst in        the second catalyst bed comprising a promoted nickel catalyst,        the high temperature water gas shift catalyst in the third        catalyst bed comprising a copper-promoted iron catalyst, and the        low temperature water shift gas catalyst in the optional fourth        catalyst bed when present in the unitary adiabatic reactor        comprising copper/zinc coated monolith catalyst, and when the        optional fourth catalyst bed is not present in the unitary        adiabatic reactor, it is present in a low temperature water gas        shift reactor external to the unitary adiabatic reactor, and        comprises the copper/zinc coated monolith catalyst;    -   (7) partial oxidation reaction being carried out in the first        catalyst bed at temperature in a range of from about 700° C. to        about 900° C., steam reforming reaction being carried out in the        second catalyst bed at temperature in a range of from about        400° C. to about 850° C., high temperature water gas shift        reaction being carried out in the third catalyst bed at        temperature in a range of from about 300° C. to about 450° C.,        and low temperature water gas shift reaction being carried out        in the optional fourth catalyst bed when present in the unitary        adiabatic reactor, or otherwise when the optional fourth        catalyst bed is not present in the unitary adiabatic reactor,        but is present in a low temperature water gas shift reactor        external to the unitary adiabatic reactor, at temperature in a        range of from about 150° C. to about 350° C.;    -   (8) the reforming comprising performance of the reaction        C₂H₅OH+(3−2x) H₂O+x O₂→(6−2x) H₂+2 CO₂ wherein 0<x<1.5, or in a        further specific embodiment wherein 0.30<x<0.50, or wherein x is        in another suitable range of values, e.g., 0.10≤x≤1.1;        0.3≤x≤0.9; 0.3≤x≤0.5; or 0.75≤x≤0.85; or x may for example be        about 0.4, 0.5, 0.65, 0.80, 1.0, or other suitable value;    -   (9) the generated hydrogen discharged from the reactor being in        a discharged gas stream at a concentration of at least 60 mol %;    -   (10) the reforming being thermally neutral and the electrolyzing        providing all oxygen required by the reforming;    -   (11) the electrolyzing being carried out in a solid oxide        electrolyzer, wherein the reforming is conducted to generate        excess heat, and wherein the excess heat generated by the        reforming is transferred to the solid oxide electrolyzer so that        the solid oxide electrolyzer operates at thermal efficiency        greater than 50%; and    -   (12) the optional fourth catalyst bed not being present in the        unitary adiabatic reactor, and being present in a low        temperature water gas shift reactor external to the unitary        adiabatic reactor.

In the practice of the present disclosure, a preferred implementation ofthe system of the present disclosure, in various embodiments, may beconstituted as a hydrogen generation system, comprising: an electrolyzerarranged to receive water and to generate hydrogen and oxygen therefrom;and a non-autothermal oxidative reforming system comprising a unitaryadiabatic reactor arranged to receive oxygen from the electrolyzer,feedstock fuel from a feedstock fuel source, and water from a watersource, the reactor containing successive catalyst beds that arecontacted in sequence in flow through the reactor, including (i) a firstcatalyst bed comprising a partial oxidation catalyst, (ii) a secondcatalyst bed comprising steam reforming catalyst, (iii) a third catalystbed comprising a high temperature water gas shift catalyst, andoptionally (iv) a fourth catalyst bed comprising a lower temperaturewater gas shift catalyst, so that feedstock fuel from the feedstock fuelsource with the oxygen from the electrolyzer and water is catalyticallyoxidatively reformed in the reactor to generate hydrogen, the reactorbeing arranged to discharge the generated hydrogen, wherein thefeedstock fuel source is arranged to supply feedstock fuel comprisingfuel selected from the group consisting of oxygenates, hydrocarbons, andmixtures thereof, the feedstock fuel having a bio-derived content in arange of from 5% to 100% by volume, based on total volume of thefeedstock fuel. Such preferred system implementation may further embodyor incorporate any one or more compatible features (1)-(13) of:

-   -   (1) the feedstock fuel source comprising a supply vessel, flow        circuitry, or reservoir containing the feedstock fuel;    -   (2) the electrolyzer and the non-autothermal oxidative reforming        system being co-located at a stationary geographic site        installation, e.g., with a separation distance between them that        is less than at least one of 10 km, 8 km, 6 km, 5 km, 4 km, 3        km, 2.5 km, 2.4 km, 2.3 km, 2.2 km, 2.1 km, 2.0 km, 1.9 km, 1.8        km, 1.7 km, 1.6 km, 1.5 km, 1.4 km, 1.3 km, 1.2 km, 1.1 km, 1.0        km, 0.9 km, 0.8 km, 0.7 km, 0.6 km, 0.5 km, 0.4 km, 0.3 km, 0.2        km, 0.1 km, 0.05 km, 0.025 km, 0.005 km, and 0.001 km;    -   (3) the hydrogen generation system being of modular form mounted        on a skid or in a commercial container for transport to and        installation at a hydrogen production site, the system being        constituted to produce hydrogen at a rate in a range of 100-2000        kg hydrogen/day;    -   (4) the feedstock fuel in the feedstock fuel source having a        bio-derived content of up to 100% by volume of the feedstock        fuel, e.g., being in a range in which the lower end point value        is 1%, 2%, 3%, 4%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, 25%, 30%,        35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%,        98%, or up to 100%, by volume, based on total volume of the        feedstock fuel, and in which the upper end point value is one of        the foregoing numeric values exceeding the lower end point value        and up to and including the value of 100% by volume;    -   (5) the optional fourth catalyst bed not being present in the        unitary adiabatic reactor, and being present in a low        temperature water gas shift reactor external to the unitary        adiabatic reactor in the hydrogen generation system;    -   (6) the feedstock fuel in the feedstock fuel source comprising a        biologically produced hydrocarbon or a biologically produced        oxygenate;    -   (7) the feedstock fuel in the feedstock fuel source comprising        ethanol;    -   (8) the electrolyzer comprising an electrolyzer selected from        the group consisting of polymer electrolyte membrane        electrolyzers, alkaline electrolyzers, and solid oxide        electrolyzers;    -   (9) the partial oxidation catalyst in the first catalyst bed        comprising a rhenium catalyst, the steam reforming catalyst in        the second catalyst bed comprising a promoted nickel catalyst,        the high temperature water gas shift catalyst in the third        catalyst bed comprising a copper-promoted iron catalyst, and the        low temperature water shift gas catalyst in the optional fourth        catalyst bed when present comprising copper/zinc coated monolith        catalyst, and when the optional fourth catalyst bed is not        present in the unitary adiabatic reactor, it is present in a low        temperature water gas shift reactor external to the unitary        adiabatic reactor, and comprises the copper/zinc coated monolith        catalyst;    -   (10) the hydrogen generation system comprising a process        controller arranged to control temperature in the reactor so        that partial oxidation reaction is carried out in the first        catalyst bed at temperature in a range of from about 700° C. to        about 900° C., steam reforming reaction is carried out in the        second catalyst bed at temperature in a range of from about        400° C. to about 850° C., high temperature water gas shift        reaction is carried out in the third catalyst bed at temperature        in a range of from about 300° C. to about 450° C., and low        temperature water gas shift reaction is carried out in the        optional fourth catalyst bed when present in the unitary        adiabatic reactor, or otherwise when the optional fourth        catalyst bed is not present in the unitary adiabatic reactor,        but is present in a low temperature water gas shift reactor        external to the unitary adiabatic reactor, at temperature in a        range of from about 150° C. to about 350° C.;    -   (11) the reactor being of vertically elongate form, arranged for        down flow of gas therethrough, with the first catalyst bed at an        uppermost position in the successive catalyst beds, overlying        the second catalyst bed, which in turn overlies the third        catalyst bed, which in turn overlies the optional fourth        catalyst bed when present, with the optional fourth catalyst bed        when present being at a lowermost position in the successive        catalyst beds, preferably wherein the successive catalyst beds        in the reactor are separated from one another by physical        separation elements or structure;    -   (12) the feedstock fuel in the feedstock fuel source comprising        ethanol, and the hydrogen generation system further comprising a        process controller arranged to coordinate operation of the        electrolyzer and non-autothermal oxidative reforming system so        that the non-autothermal oxidative reforming system carries out        the reaction C₂H₅OH+(3−2x) H₂O+x O₂→(6−2x) H₂+2 CO₂ wherein        0<x<1.5, or in a further specific embodiment wherein        0.30<x<0.50, or wherein x is in another suitable range of        values, e.g., 0.10≤x≤1.1; 0.3≤x≤0.9; 0.3≤x≤0.5; or 0.75≤x≤0.85;        or x may for example be about 0.4, 0.5, 0.65, 0.80, 1.0, or        other suitable value;    -   (13) the electrolyzer being a solid oxide electrolyzer, and the        hydrogen generation system further comprising a process        controller arranged to coordinate operation of the electrolyzer        and non-autothermal oxidative reforming system so that the        non-autothermal oxidative reforming system generates excess heat        for transfer to the solid oxide electrolyzer so that the solid        oxide electrolyzer operates at thermal efficiency greater than        50%.

In one specific embodiment (referred to hereinafter as “Embodiment I”),the disclosure relates to a thermally integrated hydrogen generationsystem, comprising: (A) an electrolyzer arranged to receive water and togenerate hydrogen gas and oxygen gas therefrom; (B) an oxygen storagevessel, arranged to receive the oxygen gas from the electrolyzer; (C) anon-autothermal oxidative reforming system comprising a unitaryadiabatic reactor arranged to receive oxygen gas from the oxygen storagevessel, feedstock fuel from a feedstock fuel source containing thefeedstock fuel, and water from a water source, the unitary adiabaticreactor containing successive catalyst beds that are contacted insequence in flow through the unitary adiabatic reactor, including (i) afirst catalyst bed comprising a partial oxidation catalyst, (ii) asecond catalyst bed comprising steam reforming catalyst, and (iii) athird catalyst bed comprising a high temperature water gas shiftcatalyst, so that the feedstock fuel from the feedstock fuel source withthe oxygen from the oxygen storage vessel and the water from the watersource is catalytically oxidatively reformed in the unitary adiabaticreactor to generate oxidatively reformed gas that is predominantlyhydrogen, the unitary adiabatic reactor being arranged to discharge thegenerated oxidatively reformed gas, (D) a first heat exchanger arrangedto receive the generated oxidatively reformed gas from the unitaryadiabatic reactor and remove heat therefrom, to produce a reducedtemperature oxidatively reformed gas; (E) a low temperature water gasshift reactor arranged to receive the reduced temperature oxidativelyreformed gas from the first heat exchanger and convert at least aportion of carbon monoxide in the reduced temperature oxidativelyreformed gas to carbon dioxide, to produce a low temperature water gasshift reaction gas of reduced carbon monoxide content, the lowtemperature water gas shift reactor including a fourth catalyst bedcomprising a low temperature water gas shift catalyst; (F) a hydrogengas purifier arranged to receive the low temperature water gas shiftreaction gas of reduced carbon monoxide content from the low temperaturewater gas shift reactor, and to produce a separated hydrogen gas, andwaste gas containing CO, CO₂, methane, and unrecovered (residual)hydrogen; (G) a hydrogen gas reservoir, arranged to receive the hydrogengas from the electrolyzer and the separated hydrogen gas from thehydrogen gas purifier; (H) a burner arranged to combust the waste gasproduced by the hydrogen gas purifier, to yield a flue gas; (I) a secondheat exchanger arranged to receive the flue gas from the burner forheating of the oxygen gas from the oxygen storage vessel, the feedstockfuel from the feedstock fuel source, and the water from the water sourceprior to their introduction to the unitary adiabatic reactor; and (J) aprocess controller configured and arranged to coordinate operation ofthe electrolyzer and the non-autothermal oxidative reforming system inthe thermally integrated hydrogen generation system, and adjustthroughput of each of the electrolyzer and the non-autothermal oxidativereforming system to control temperature in the unitary adiabaticreactor, wherein the feedstock fuel contained in the feedstock fuelsource comprises fuel selected from the group consisting of oxygenates,hydrocarbons, and mixtures thereof, the feedstock fuel having abio-derived content of up to 100% by volume of the feedstock fuel, e.g.,in a range of from 1% to 100% by volume, based on total volume of thefeedstock fuel.

Embodiment I may be implemented with any one or more of the followingcompatible features: (1) the feedstock fuel source comprising a supplyvessel, flow circuitry, or reservoir containing the feedstock fuel; (2)the electrolyzer and the non-autothermal oxidative reforming systembeing co-located at a stationary geographic site installation, e.g.,with a separation distance between them that is less than at least oneof 10 km, 8 km, 6 km, 5 km, 4 km, 3 km, 2.5 km, 2.4 km, 2.3 km, 2.2 km,2.1 km, 2.0 km, 1.9 km, 1.8 km, 1.7 km, 1.6 km, 1.5 km, 1.4 km, 1.3 km,1.2 km, 1.1 km, 1.0 km, 0.9 km, 0.8 km, 0.7 km, 0.6 km, 0.5 km, 0.4 km,0.3 km, 0.2 km, 0.1 km, 0.05 km, 0.025 km, 0.005 km, and 0.001 km; (3)the hydrogen generation system being of modular form mounted on a skidor in a commercial container for transport to and installation at ahydrogen production site, the system being constituted to producehydrogen at a rate in a range of 100-2000 kg hydrogen/day; (4) thefeedstock fuel contained in the feedstock fuel source having abio-derived content of up to 100% by volume of the feedstock fuel, e.g.,being in a range in which the lower end point value is 1%, 2%, 3%, 4%,5%, 8%, 10%, 12%, 15%, 18%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%,65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or up to 100%, by volume, basedon volume of the feedstock fuel, and in which the upper end point valueis one of the foregoing numeric values exceeding the lower end pointvalue and up to and including the value of 100% by volume; (5) theprocess controller being configured and arranged to adjust throughput ofeach of the electrolyzer and the non-autothermal oxidative reformingsystem in response to variability of the feedstock fuel and variabilityof electricity costs; (6) the feedstock fuel contained in the feedstockfuel source comprising a biologically produced hydrocarbon or abiologically produced oxygenate; (7) the feedstock fuel contained in thefeedstock fuel source comprising ethanol; (8) the electrolyzercomprising an electrolyzer selected from the group consisting of polymerelectrolyte membrane electrolyzers, alkaline electrolyzers, and solidoxide electrolyzers; (9) the partial oxidation catalyst in the firstcatalyst bed comprising a rhodium catalyst, the steam reforming catalystin the second catalyst bed comprising a promoted nickel catalyst, thehigh temperature water gas shift catalyst in the third catalyst bedcomprising a copper-promoted iron catalyst, and the low temperaturewater shift gas catalyst in the fourth catalyst bed comprisingcopper/zinc coated monolith catalyst; (10) the process controller beingconfigured and arranged to control temperature in the unitary adiabaticreactor so that partial oxidation reaction is carried out in the firstcatalyst bed at temperature in a range of from about 700° C. to about900° C., steam reforming reaction is carried out in the second catalystbed at temperature in a range of from about 450° C. to about 850° C.,high temperature water gas shift reaction is carried out in the thirdcatalyst bed at temperature in a range of from about 300° C. to about450° C., and low temperature water gas shift reaction is carried out inthe fourth catalyst bed at temperature in a range of from about 150° C.to about 350° C.; (11) the unitary adiabatic reactor being of verticallyelongate form, arranged for down flow of gas therethrough, with thefirst catalyst bed at an uppermost position in the successive catalystbeds, overlying the second catalyst bed, which in turn overlies thethird catalyst bed, with the third catalyst bed being at a lowermostposition in the successive catalyst beds; (12) the successive catalystbeds in the unitary adiabatic reactor are separated from one another byphysical separation elements or structure; (13) the feedstock fuelcontained in the feedstock fuel source comprising ethanol, and theprocess controller being configured and arranged to coordinate operationof the electrolyzer and non-autothermal oxidative reforming system sothat the non-autothermal oxidative reforming system carries out thereaction C₂H₅OH+(3−2x) H₂O+x O₂→(6−2x) H₂+2 CO₂, wherein x is specifiedby any of: 0<x<1.5; 0.10≤x≤1.1; 0.3≤x≤0.9; 0.3≤x≤0.5; 0.75≤x≤0.85, orwherein x is about 0.4, 0.5, 0.65, 0.80, or 1.0; (14) the electrolyzeris a solid oxide electrolyzer, and the process controller is configuredand arranged to coordinate operation of the electrolyzer andnon-autothermal oxidative reforming system so that the non-autothermaloxidative reforming system generates excess heat for transfer to thesolid oxide electrolyzer so that the solid oxide electrolyzer operatesat thermal efficiency greater than 50%; (15) comprising an ethanolrefinery that produces ethanol as a fermentation product from afermentable feedstock, wherein the ethanol refinery is arranged tosupply at least part of the feedstock fuel for the non-autothermaloxidative reforming system; (16) the electrolyzer and thenon-autothermal oxidative reforming system being arranged to exportwaste heat to fermentation and distillation apparatus of the ethanolrefinery; (17) a CO₂ processing or carbon capture system arranged toreceive CO₂ gas from each of the ethanol refinery and thenon-autothermal oxidative reforming system.

In another specific embodiment (referred to hereinafter as “EmbodimentII”), the disclosure relates to a hydrogen generation process,comprising operating the thermally integrated hydrogen generation systemdescribed immediately above to perform a hydrogen generation processcomprising: electrolyzing water to generate hydrogen gas and oxygen gastherefrom; and non-autothermally catalytically oxidatively reforming thefeedstock fuel with said oxygen gas and with water from the water sourceto generate hydrogen.

Embodiment II may be implemented with any one or more of the followingfeatures: (1) the bio-derived content of the feedstock fuel being up to100% by volume of the feedstock fuel, e.g., being in a range in whichthe lower end point value is 1%, 2%, 3%, 4%, 5%, 8%, 10%, 12%, 15%, 18%,20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%,90%, 95%, 98%, or up to 100%, by volume, based on volume of thefeedstock fuel, and in which the upper end point value is one of theforegoing numeric values exceeding the lower end point value and up toand including the value of 100% by volume; (2) the feedstock fuelcomprising a biologically produced hydrocarbon; (3) the feedstock fuelcomprising a biologically produced oxygenate; (4) the feedstock fuelcomprising ethanol; (5) the electrolyzing being carried out in anelectrolyzer selected from the group consisting of polymer electrolytemembrane electrolyzers, alkaline electrolyzers, and solid oxideelectrolyzers; (6) the partial oxidation catalyst in the first catalystbed comprising a rhodium catalyst, the steam reforming catalyst in thesecond catalyst bed comprising a promoted nickel catalyst, the hightemperature water gas shift catalyst in the third catalyst bedcomprising a copper-promoted iron catalyst, and the low temperaturewater gas shift catalyst in the fourth catalyst bed comprisingcopper/zinc coated monolith catalyst; (7) the partial oxidation reactionbeing carried out in the first catalyst bed at temperature in a range offrom about 700° C. to about 900° C., steam reforming reaction beingcarried out in the second catalyst bed at temperature in a range of fromabout 400° C. to about 850° C., high temperature water gas shiftreaction being carried out in the third catalyst bed at temperature in arange of from about 300° C. to about 450° C., and low temperature watergas shift reaction being carried out in the fourth catalyst bed in thelow temperature water gas shift reactor at temperature in a range offrom about 150° C. to about 350° C.; (8) wherein x is specified by anyof: 0<x<1.5; 0.10≤x≤1.1; 0.3≤x≤0.9; 0.3≤x≤0.5; 0.75≤x≤0.85, or wherein xis about 0.4, 0.5, 0.65, 0.80, or 1.0; (9) the hydrogen generated in thenon-autothermally catalytically oxidatively reforming being dischargedfrom the unitary adiabatic reactor in a discharged gas stream at aconcentration of at least 60 mol %; (10) the non-autothermallycatalytically oxidatively reforming being thermally neutral and theelectrolyzing providing all oxygen required by the non-autothermallycatalytically oxidatively reforming; (11) the electrolyzing beingcarried out in a solid oxide electrolyzer, wherein the non-autothermallycatalytically oxidatively reforming is conducted to generate excessheat, and wherein the excess heat generated by the non-autothermallycatalytically oxidatively reforming is transferred to the solid oxideelectrolyzer so that the solid oxide electrolyzer operates at thermalefficiency greater than 50%; (12) the throughput of each of theelectrolyzer and the non-autothermal oxidative reforming system beingadjusted by the process controller in response to variability of thefeedstock fuel and variability of electricity costs; (13) producingethanol as a fermentation product from a fermentable feedstock in anethanol refinery, and supplying the ethanol from the ethanol refinery asat least part of the feedstock fuel for the non-autothermal oxidativereforming system; (14) the electrolyzer and the non-autothermaloxidative reforming system being arranged to export waste heat tofermentation and distillation apparatus of the ethanol refinery; and(15) treating CO₂ gas in a CO₂ processing or carbon capture systemarranged to receive CO₂ gas from each of the ethanol refinery and thenon-autothermal oxidative reforming system.

In various other embodiments of the disclosure, any one or more of thefeatures (1)-(17) specified above for Embodiment I and any one or moreof the features (1)-(15) specified above for Embodiment II mayindependently be implemented in the systems and processes of thedisclosure, as further embodiments of the disclosure.

Various other additional embodiments of the disclosure are set forthbelow.

Embodiment 1: A hydrogen production process, comprising: (a)electrolyzing water to generate hydrogen gas and oxygen gas therefrom,the generated hydrogen gas being a first hydrogen component of thehydrogen production; (b) adiabatically and non-autothermallycatalytically oxidatively reforming a feedstock comprising at least oneof an oxygenate and a hydrocarbon, with water and with high purityoxygen comprising at least a portion of the oxygen gas generated by theelectrolyzing, to produce oxidative reforming reaction product gascontaining hydrogen, CO, CO₂, methane, and steam; (c) catalyticallyreacting the oxidative reforming reaction product gas in a catalyticwater gas shift reaction to convert at least part of the CO in theoxidative reforming reaction product gas to CO₂ and hydrogen by reactionwith the steam therein, to produce a water gas shift reaction productgas containing hydrogen, methane, CO, and CO₂; and (d) separating thewater gas shift reaction product gas to recover hydrogen gas therefromas a second hydrogen component of the hydrogen production.

Embodiment 2: The hydrogen production process of Embodiment 1, whereinthe electrolyzing (a) generates from 15% to 60% of the hydrogenproduction of the hydrogen production process, and all of the highpurity oxygen required for adiabatically and non-autothermallycatalytically oxidatively reforming the feedstock.

Embodiment 3: The hydrogen production process of Embodiment 1, whereinthe separating (d) of the water gas shift reaction product gas torecover hydrogen gas therefrom produces a waste gas containing CO, CO₂,methane, and unrecovered hydrogen, the process further comprising: (e)heating the feedstock, water, and oxygen gas of (b) prior to theadiabatically and non-autothermally catalytically oxidatively reforming,by heat produced by combusting the waste gas.

Embodiment 4: The hydrogen production process of Embodiment 1, whereinthe adiabatically and non-autothermally catalytically oxidativelyreforming is conducted in a unitary non-autothermal adiabatic reactor.

Embodiment 5: The hydrogen production process of Embodiment 4, wherein(c) catalytically reacting the oxidative reforming reaction product gasin a catalytic water gas shift reaction is carried out at leastpartially in the unitary non-autothermal adiabatic reactor.

Embodiment 6: The hydrogen production process of Embodiment 1, wherein(c) catalytically reacting the oxidative reforming reaction product gasin a catalytic water gas shift reaction comprises a higher temperaturecatalytic water gas shift reaction producing a higher temperaturecatalytic water gas shift reaction product gas that then undergoes asubsequent lower temperature catalytic water gas shift reaction toproduce the water gas shift reaction product gas.

Embodiment 7: The hydrogen production process of Embodiment 6, whereinthe higher temperature catalytic water gas shift reaction product gasprior to undergoing the subsequent lower temperature catalytic water gasshift reaction is heat exchanged with the feedstock and water of (b) forfurther heating thereof prior to the adiabatically and non-autothermallycatalytically oxidatively reforming.

Embodiment 8: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises a non-bio-derived feedstock.

Embodiment 9: The hydrogen production process of Embodiment 8, whereinthe non-bio-derived feedstock comprises feedstock selected from thegroup consisting of: natural gas; C₂-C₁₅ hydrocarbons; alcohols; andblends of two or more of the foregoing.

Embodiment 10: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises a bio-derived feedstock.

Embodiment 11: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises at least one of a biologically producedhydrocarbon and a biologically produced oxygenate.

Embodiment 12: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises ethanol.

Embodiment 13: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises bioethanol.

Embodiment 14: The hydrogen production process of Embodiment 1, whereinthe electrolyzing is carried out in an electrolyzer selected from thegroup consisting of polymer electrolyte membrane electrolyzers, alkalineelectrolyzers, and solid oxide electrolyzers.

Embodiment 15: The hydrogen production process of Embodiment 1, whereinthe adiabatically and non-autothermally catalytically oxidativelyreforming (b) comprises partial oxidation catalytic reaction andsubsequent catalytic steam reforming reaction.

Embodiment 16: The hydrogen production process of Embodiment 15, whereinthe partial oxidation catalytic reaction is conducted with a rhodiumcatalyst and the catalytic steam reforming reaction is conducted with apromoted nickel catalyst.

Embodiment 17: The hydrogen production process of Embodiment 1, wherein(c) catalytically reacting the oxidative reforming reaction product gasin a catalytic water gas shift reaction comprises a higher temperaturecatalytic water gas shift reaction producing a higher temperaturecatalytic water gas shift reaction product gas that then undergoes asubsequent lower temperature catalytic water gas shift reaction toproduce the water gas shift reaction product gas, wherein the highertemperature catalytic water gas shift reaction is conducted with acopper-promoted iron catalyst, and the lower temperature catalytic watergas shift reaction is conducted with a copper/zinc catalyst.

Embodiment 18: The hydrogen production process of Embodiment 15, whereinthe partial oxidation catalytic reaction is conducted at temperature ina range of from about 700° C. to about 900° C., and the catalytic steamreforming reaction is conducted at temperature in a range of from about400° C. to about 850° C.

Embodiment 19: The hydrogen production process of Embodiment 1, wherein(c) catalytically reacting the oxidative reforming reaction product gasin a catalytic water gas shift reaction comprises a higher temperaturecatalytic water gas shift reaction producing a higher temperaturecatalytic water gas shift reaction product gas that then undergoes asubsequent lower temperature catalytic water gas shift reaction toproduce the water gas shift reaction product gas, wherein the highertemperature catalytic water gas shift reaction is conducted attemperature in a range of from about 300° C. to about 450° C., and thelower temperature catalytic water gas shift reaction is conducted attemperature in a range of from about 150° C. to about 350° C.

Embodiment 20: The hydrogen production process of Embodiment 1, wherein(b) adiabatically and non-autothermally catalytically oxidativelyreforming comprises performance of reaction (1):

C₂H₅OH+(3−2x)H₂O+x O₂→(6−2x)H₂+2 CO₂  (1)

wherein 0<x<1.5.

Embodiment 21: The hydrogen production process of Embodiment 20, whereinthe reforming (b) is conducted at a molar ratio of steam to ethanol in arange of from 0 to 6, and a molar ratio of oxygen to ethanol in a rangeof from 0.1 to 1.

Embodiment 22: The hydrogen production process of Embodiment 1, whereinthe adiabatically and non-autothermally catalytically oxidativelyreforming (b) is thermally neutral and the electrolyzing provides alloxygen required by the reforming.

Embodiment 23: The hydrogen production process of Embodiment 1, whereinthe electrolyzing is carried out in a solid oxide electrolyzer, whereinthe adiabatically and non-autothermally catalytically oxidativelyreforming (b) is conducted to generate excess heat, and wherein theexcess heat generated by the non-autothermally catalytically oxidativelyreforming (b) is transferred to the solid oxide electrolyzer so that thesolid oxide electrolyzer operates at thermal efficiency greater than50%.

Embodiment 24: The hydrogen production process of Embodiment 1, whereinat least part of the feedstock is supplied by an ethanol refineryproducing ethanol as a fermentation product from a fermentablefeedstock.

Embodiment 25: The hydrogen production process of Embodiment 24, whereinCO₂ produced by the ethanol refinery and CO₂ produced by the hydrogenproduction process are treated in a CO₂ processing or carbon capturesystem arranged to receive CO₂ gas from each of the ethanol refinery andthe hydrogen production process.

Embodiment 26: The hydrogen production process of Embodiment 24, whereinwaste heat of the hydrogen production process is exported tofermentation and distillation apparatus of the ethanol refinery.

Embodiment 27: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises methane, and (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (2):

2 CH₄ +x O₂+(4−2x)H₂O=(8−2x)H₂+2 CO₂  (2)

wherein x is in a range of from 0.5 to 2.0, andwherein (b) adiabatically and non-autothermally catalyticallyoxidatively reforming operation is thermally neutral at x=0.7.

Embodiment 28: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises methanol, and (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (3):

CH₃OH+x O₂+(1−2x)H₂O=(3−2x)H₂+CO₂  (3)

wherein x is in a range of from 0.1 to 0.5, andwherein (b) adiabatically and non-autothermally catalyticallyoxidatively reforming operation is thermally neutral at x=0.15.

Embodiment 29: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises one or more hydrocarbons, and (b) adiabaticallyand non-autothermally catalytically oxidatively reforming comprisesperformance of reaction (4):

C_(n)H_(m) +x O₂+(2n−2x)H₂O=(2n−2x+m/2)H₂ +n CO₂  (4)

wherein x is in a range of from 0.4 to 14, for values of n=2-15, and mis a number compatible with n for each of said one or more hydrocarbons.

Embodiment 30: The hydrogen production process of Embodiment 1, whereinthe feedstock comprises glycerol, and (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (5):

C₃H₈O₃ +x O₂+(3−2x)H₂O=(7−2x)H₂+3 CO₂  (5)

wherein x is in a range of from 0.2 to 1.2.

A listing of drawing reference numerals for the drawings of the presentdisclosure is set out below.

-   -   10 hydrogen gas generation system    -   11 non-autothermal oxidative reforming system    -   12 non-autothermal oxidative reforming system    -   14 low temperature electrolysis system    -   16 water-ethanol supply line    -   18 feedstock blender    -   20 heat exchanger    -   22 feedstock delivery line    -   24 heat exchanger    -   26 flue gas line    -   28 non-autothermal oxidative reforming reactor    -   30 non-autothermal oxidative reforming reactor discharge line    -   32 burner    -   33 burner oxygen/air feed line    -   34 low temperature water gas shift reactor    -   36 low temperature water gas shift reactor discharge line    -   38 hydrogen gas purifier    -   40 hydrogen gas discharge line    -   42 waste gas discharge line    -   44 oxygen feed line    -   46 carbon dioxide recovery vessel    -   48 carbon dioxide discharge line    -   49 recycle water discharge line    -   50 feed water source    -   52 feed water pump    -   54 water filter/purifier    -   56 oxygen-water phase separation and supply vessel    -   58 water feed line    -   60 water circulation pump    -   62 heat exchanger    -   64 ion exchanger    -   66 PEM electrolyzer    -   68 oxygen discharge line    -   70 oxygen demister vessel    -   72 oxygen discharge line    -   73 oxygen storage vessel    -   74 flow control valve    -   76 hydrogen outlet line    -   78 gas-liquid separator vessel    -   80 hydrogen delivery line    -   82 hydrogen demister vessel    -   84 heat exchanger    -   86 condensate trap    -   88 flow control valve    -   90 hydrogen gas storage reservoir    -   92 hydrogen compressor    -   94 hydrogen discharge line    -   96 hydrogen supply line    -   98 flow control valve    -   100 hydrogen gas generation system    -   102 high temperature solid oxide electrolyzer    -   104 hydrogen/steam discharge line    -   106 oxygen/steam discharge line    -   108 heat exchanger    -   110 makeup water supply line    -   112 heat exchanger    -   114 oxygen/water separator    -   116 heat exchanger    -   118 heat exchanger    -   120 thermal recovery assembly    -   122 knock-out pot    -   124 hydrogen discharge line    -   126 high temperature electrolysis system    -   128 electrolyzer recycle line    -   130 flow control valve    -   132 process controller    -   134 bidirectional signal transmission line    -   136 bidirectional signal transmission line    -   140 process controller    -   142 bidirectional signal transmission line    -   144 bidirectional signal transmission line

While the disclosure has been set forth herein in reference to specificaspects, features and illustrative embodiments, it will be appreciatedthat the utility of the disclosure is not thus limited, but ratherextends to and encompasses numerous other variations, modifications andalternative embodiments, as will suggest themselves to those of ordinaryskill in the field of the present disclosure, based on the descriptionherein. Correspondingly, the disclosure as hereinafter claimed isintended to be broadly construed and interpreted, as including all suchvariations, modifications and alternative embodiments, within its spiritand scope.

What is claimed is:
 1. A hydrogen production process, comprising: (a)electrolyzing water to generate hydrogen gas and oxygen gas therefrom,the generated hydrogen gas being a first hydrogen component of thehydrogen production; (b) adiabatically and non-autothermallycatalytically oxidatively reforming a feedstock comprising at least oneof an oxygenate and a hydrocarbon, with water and with high purityoxygen comprising at least a portion of the oxygen gas generated by theelectrolyzing, to produce oxidative reforming reaction product gascontaining hydrogen, CO, CO₂, methane, and steam; (c) catalyticallyreacting the oxidative reforming reaction product gas in a catalyticwater gas shift reaction to convert at least part of the CO in theoxidative reforming reaction product gas to CO₂ and hydrogen by reactionwith the steam therein, to produce a water gas shift reaction productgas containing hydrogen, methane, CO, and CO₂; and (d) separating thewater gas shift reaction product gas to recover hydrogen gas therefromas a second hydrogen component of the hydrogen production.
 2. Thehydrogen production process of claim 1, wherein the electrolyzing (a)generates from 15% to 60% of the hydrogen production of the hydrogenproduction process, and all of the high purity oxygen required foradiabatically and non-autothermally catalytically oxidatively reformingthe feedstock.
 3. The hydrogen production process of claim 1, whereinthe separating (d) of the water gas shift reaction product gas torecover hydrogen gas therefrom produces a waste gas containing CO, CO₂,methane, and unrecovered hydrogen, the process further comprising: (e)heating the feedstock, water, and oxygen gas of (b) prior to theadiabatically and non-autothermally catalytically oxidatively reforming,by heat produced by combusting the waste gas.
 4. The hydrogen productionprocess of claim 1, wherein the adiabatically and non-autothermallycatalytically oxidatively reforming is conducted in a unitarynon-autothermal adiabatic reactor.
 5. The hydrogen production process ofclaim 4, wherein (c) catalytically reacting the oxidative reformingreaction product gas in a catalytic water gas shift reaction is carriedout at least partially in the unitary non-autothermal adiabatic reactor.6. The hydrogen production process of claim 1, wherein (c) catalyticallyreacting the oxidative reforming reaction product gas in a catalyticwater gas shift reaction comprises a higher temperature catalytic watergas shift reaction producing a higher temperature catalytic water gasshift reaction product gas that then undergoes a subsequent lowertemperature catalytic water gas shift reaction to produce the water gasshift reaction product gas.
 7. The hydrogen production process of claim6, wherein the higher temperature catalytic water gas shift reactionproduct gas prior to undergoing the subsequent lower temperaturecatalytic water gas shift reaction is heat exchanged with the feedstockand water of (b) for further heating thereof prior to the adiabaticallyand non-autothermally catalytically oxidatively reforming.
 8. Thehydrogen production process of claim 1, wherein the feedstock comprisesa non-bio-derived feedstock.
 9. The hydrogen production process of claim8, wherein the non-bio-derived feedstock comprises feedstock selectedfrom the group consisting of: natural gas; C₂-C₁₅ hydrocarbons;alcohols; and blends of two or more of the foregoing.
 10. The hydrogenproduction process of claim 1, wherein the feedstock comprises abio-derived feedstock.
 11. The hydrogen production process of claim 1,wherein the feedstock comprises at least one of a biologically producedhydrocarbon and a biologically produced oxygenate.
 12. The hydrogenproduction process of claim 1, wherein the feedstock comprises ethanol.13. The hydrogen production process of claim 1, wherein the feedstockcomprises bioethanol.
 14. The hydrogen production process of claim 1,wherein the electrolyzing is carried out in an electrolyzer selectedfrom the group consisting of polymer electrolyte membrane electrolyzers,alkaline electrolyzers, and solid oxide electrolyzers.
 15. The hydrogenproduction process of claim 1, wherein the adiabatically andnon-autothermally catalytically oxidatively reforming (b) comprisespartial oxidation catalytic reaction and subsequent catalytic steamreforming reaction.
 16. The hydrogen production process of claim 15,wherein the partial oxidation catalytic reaction is conducted with arhodium catalyst and the catalytic steam reforming reaction is conductedwith a promoted nickel catalyst.
 17. The hydrogen production process ofclaim 1, wherein (c) catalytically reacting the oxidative reformingreaction product gas in a catalytic water gas shift reaction comprises ahigher temperature catalytic water gas shift reaction producing a highertemperature catalytic water gas shift reaction product gas that thenundergoes a subsequent lower temperature catalytic water gas shiftreaction to produce the water gas shift reaction product gas, whereinthe higher temperature catalytic water gas shift reaction is conductedwith a copper-promoted iron catalyst, and the lower temperaturecatalytic water gas shift reaction is conducted with a copper/zinccatalyst.
 18. The hydrogen production process of claim 15, wherein thepartial oxidation catalytic reaction is conducted at temperature in arange of from about 700° C. to about 900° C., and the catalytic steamreforming reaction is conducted at temperature in a range of from about400° C. to about 850° C.
 19. The hydrogen production process of claim 1,wherein (c) catalytically reacting the oxidative reforming reactionproduct gas in a catalytic water gas shift reaction comprises a highertemperature catalytic water gas shift reaction producing a highertemperature catalytic water gas shift reaction product gas that thenundergoes a subsequent lower temperature catalytic water gas shiftreaction to produce the water gas shift reaction product gas, whereinthe higher temperature catalytic water gas shift reaction is conductedat temperature in a range of from about 300° C. to about 450° C., andthe lower temperature catalytic water gas shift reaction is conducted attemperature in a range of from about 150° C. to about 350° C.
 20. Thehydrogen production process of claim 1, wherein (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (1):C₂H₅OH+(3−2x)H₂O+x O₂→(6−2x)H₂+2CO₂  (1) wherein 0<x<1.5.
 21. Thehydrogen production process of claim 20, wherein the reforming (b) isconducted at a molar ratio of steam to ethanol in a range of from 0 to6, and a molar ratio of oxygen to ethanol in a range of from 0.1 to 1.22. The hydrogen production process of claim 1, wherein theadiabatically and non-autothermally catalytically oxidatively reforming(b) is thermally neutral and the electrolyzing provides all oxygenrequired by the reforming.
 23. The hydrogen production process of claim1, wherein the electrolyzing is carried out in a solid oxideelectrolyzer, wherein the adiabatically and non-autothermallycatalytically oxidatively reforming (b) is conducted to generate excessheat, and wherein the excess heat generated by the non-autothermallycatalytically oxidatively reforming (b) is transferred to the solidoxide electrolyzer so that the solid oxide electrolyzer operates atthermal efficiency greater than 50%.
 24. The hydrogen production processof claim 1, wherein at least part of the feedstock is supplied by anethanol refinery producing ethanol as a fermentation product from afermentable feedstock.
 25. The hydrogen production process of claim 24,wherein CO₂ produced by the ethanol refinery and CO₂ produced by thehydrogen production process are treated in a CO₂ processing or carboncapture system arranged to receive CO₂ gas from each of the ethanolrefinery and the hydrogen production process.
 26. The hydrogenproduction process of claim 24, wherein waste heat of the hydrogenproduction process is exported to fermentation and distillationapparatus of the ethanol refinery.
 27. The hydrogen production processof claim 1, wherein the feedstock comprises methane, and (b)adiabatically and non-autothermally catalytically oxidatively reformingcomprises performance of reaction (2):2CH₄ +x O₂+(4−2x)H₂O=(8−2x)H₂+2CO₂  (2) wherein x is in a range of from0.5 to 2.0, and wherein (b) adiabatically and non-autothermallycatalytically oxidatively reforming operation is thermally neutral atx=0.7.
 28. The hydrogen production process of claim 1, wherein thefeedstock comprises methanol, and (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (3):CH₃OH+x O₂+(1−2x)H₂O=(3−2x)H₂+CO₂  (3) wherein x is in a range of from0.1 to 0.5, and wherein (b) adiabatically and non-autothermallycatalytically oxidatively reforming operation is thermally neutral atx=0.15.
 29. The hydrogen production process of claim 1, wherein thefeedstock comprises one or more hydrocarbons, and (b) adiabatically andnon-autothermally catalytically oxidatively reforming comprisesperformance of reaction (4):C_(n)H_(m) +x O₂+(2n−2x)H₂O=(2n−2x+m/2)H₂ +n CO₂  (4) wherein x is in arange of from 0.4 to 14, for values of n=2-15, and m is a numbercompatible with n for each of said one or more hydrocarbons.
 30. Thehydrogen production process of claim 1, wherein the feedstock comprisesglycerol, and (b) adiabatically and non-autothermally catalyticallyoxidatively reforming comprises performance of reaction (5):C₃H₈O₃ +x O₂+(3−2x)H₂O=(7−2x)H₂+3 CO₂  (5) wherein x is in a range offrom 0.2 to 1.2.